Compare Shark HP201 vs Alen BreatheSmart 35i

The carbon layer is viewed as solid but not class-leading for odors. One comparison says the Shark filter has enough carbon for particles while another purifier may be stronger on smells.

Optional carbon filtration is appreciated for odor and gas coverage, but expert evidence says the carbon amount is limited for serious VOC problems.

The strongest air-change guidance favors medium rooms over the full advertised maximum. One expert estimated better turnover around 400 to 450 square feet.

Expert testing supports useful air changes only in smaller rooms, with quiet-speed coverage falling below average bedroom sizing.

Air movement feels strong to many buyers, sometimes powerful enough to be overkill in small rooms. One Spanish-language reviewer wished it had more reach for a whole apartment.

Most owners say the HP201 makes rooms feel cleaner or fresher, often noticing the change quickly. A smaller group says their unit did not seem to clean effectively or failed after a period of good performance.

Most reviewers say the purifier improves air quality or works well, though one customer reported poor cleaning performance.

Sensor accuracy is the most polarized feature: many owners love seeing it react quickly to smoke, cooking, candles, perfume, or dust. The main bad pattern is defective or clogged sensors reading 100%, 0%, or nonsense values.

Experts and customers consistently praise the sensor as responsive, precise, and aligned with external measurements.

Allergy relief is a common positive theme, with several owners saying sneezing, stuffiness, or family allergy symptoms improved. Pet and dust-heavy households mention this benefit most often.

Allergy-related feedback is strongly positive, including customer relief and third-party asthma/allergy suitability evidence.

App connectivity is a clear drawback in the expert review because the HP201 lacks a smart app. Buyers who want connected controls may find that missing.

The app is usually praised for control and monitoring, but one expert/customer thread flags setup or registration friction.

Auto mode is widely liked because it reacts to cooking, odors, smoke, and particles without babysitting. Complaints come from sensor failures that make auto mode run constantly or change speeds annoyingly.

Auto mode is praised when the laser sensor responds quickly, but one customer reported a defective unit that did not ramp up.

Breathing relief is a real strength in allergy-sensitive homes. Reviewers mention easier breathing, less morning stuffiness, and meaningful improvement for people with respiratory discomfort.

Build quality is mostly viewed as sturdy or high quality when new. A few disappointed owners expected more from the Shark name when durability or controls failed.

Build quality is split: HouseFresh praises it, while Live Science and customers cite plastic, cheap feel, or rattling.

CADR evidence supports capable small-room performance, not large-space strength.

Child lock is seen as useful for families and homes with curious kids or pets. Reviewers like being able to stop accidental button presses.

Child lock is liked by reviewers who want to prevent accidental control changes.

Arrival condition is mostly fine when mentioned, but a few buyers received missing instructions or suspicious secondary packaging. One delivery was praised for protective double boxing.

Controls are usually simple, but one buyer reported a touch fan-speed control that was not responsive. Expert walkthroughs otherwise describe the touch buttons as straightforward.

Customer support receives mixed but often helpful feedback. Some buyers praise Shark support or replacements, while others describe difficult calls or only partial discount offers.

Customer support evidence is mixed, with one defective-unit response but another customer calling AI support useless.

Design is a consistent positive: reviewers call it sleek, stylish, good-looking, and not an eyesore. The white version and overall appearance get specific praise.

Design feedback is mostly positive for compact, unobtrusive looks, with one expert less impressed by the plastic body.

Display feedback is helpful for many buyers, but readability and meaning can be confusing. Complaints mention cryptic scoring, a wrong display value, or bright lights unless sleep mode is used.

Light and display feedback is positive, especially color-coded air quality and auto-dimming for bedrooms.

Documentation is uneven. Some owners found the instructions easy, while others said key sensor-cleaning information was missing or the manual was absent or wrong.

Durability is mixed. Some owners report good longevity over many months or nearly two years, while others had units fail suddenly, sometimes around one or two years.

Durability concerns center on rattling after months and flimsier plastic housing.

Dust reduction is one of the clearest strengths, especially in homes with pets, fields, cooking, or visible buildup. A few buyers still found dust on the unit or nearby surfaces and felt disappointed.

Dust evidence is mixed: experts measured dust-related removal, while one customer said dust buildup did not improve.

Setup and daily use are easy for most owners, with simple controls and quick assembly. The main control complaint is an unresponsive touch fan-speed button on one returned-looking unit.

Setup and controls are repeatedly described as easy, intuitive, or plug-and-use.

Eco mode is appreciated for saving energy and filter life after the room reaches clean air. Reviewers like that it can settle down instead of running hard all the time.

Efficiency evidence is moderate: experts place energy cost mid-pack, while one customer calls it quiet and efficient.

Fan speed controls give useful manual range, though some owners dislike the way speeds jump or get loud at higher levels. Multiple settings and auto mode make everyday use flexible.

Fan-speed evidence is factual but positive enough in expert context because four speeds support usable control.

Replacement availability is favorable when buyers can find filters on Amazon. The easier availability is offset by concerns about official filter pricing.

Filter availability is supported by long-term brand availability and subscription mentions.

Filter life varies by home and use. Some owners go six months without changing it, while smoke-heavy use and one negative review describe much shorter filter life.

Filter life is polarized: experts cite 6-12 months, some customers like long life, and others saw dirty filters in four months.

Replacement filter cost is a recurring pain point. Buyers call Shark’s filter pricing excessive, mention an $80 filter, or look for cheaper aftermarket options.

Filter replacement cost is one of the clearest concerns, though a few customers accept it because replacements are less frequent.

Filter construction is seen as large and capable, with a pre-filter and HEPA layer called out. Large filter capacity is a plus for owners running the unit continuously.

Filter customization and multiple filter types are praised by expert reviewers.

Handle design is praised because it helps make the unit easy to move.

The HEPA-style filtration is discussed positively in the expert walkthrough, mainly as part of the substantial internal filter design. Customer reviews focus more on results than the filter standard itself.

HEPA filtration is evaluated positively in expert discussion of particle and allergy coverage.

Indicator lights help communicate air quality status clearly. The expert walkthrough calls out color changes as part of the basic feedback system.

The filter indicator is praised because it reduces guessing about replacement timing.

Maintenance is easy for basic filter replacement, but sensor cleaning is a real frustration. Several owners say clogged sensors are hard to access or not explained well enough.

Maintenance is praised for easy filter access, low-maintenance use, and a strong filter-lock design.

Noise is split: many owners call it quiet or whisper quiet, especially on low or normal operation. High speed, red-zone cleaning, and heavy odor/smoke events can get loud enough to affect TV or sleep-sensitive use.

Noise feedback is strongly positive overall, but a few customers report weird sounds or rattling.

Odor removal is a major crowd-pleaser for cooking smells, pets, litter boxes, candles, and smoking. A few disappointed buyers said musty or pet smells were not reduced well enough.

Odor reduction is one of the strongest customer-backed benefits, especially for pets, smoke odor, cooking, and basement smells.

Overall satisfaction is high among owners whose units work correctly, with many saying they love it, would buy again, or wish they had bought more. Dissatisfied reviews concentrate on failed sensors, short lifespan, and poor perceived value.

Overall satisfaction is high across experts and most customers, offset by a few sharp negative experiences.

Particle removal gets strong marks when reviewers see it react to cooking, dust, or airborne debris. Praise centers on quick recognition and visible improvement rather than lab-style measurements.

Particle removal is strongly supported by expert test results, including near-complete removal in timed tests.

Pet households often report less dander and cleaner-feeling air around dogs, cats, and birds. This is a recurring reason people recommend it for allergy-prone homes.

Pet dander and animal-related feedback is positive, especially in homes with dogs and cats.

Pet hair and fur performance is generally positive, with many pet owners seeing less hair and dust. One Spanish-language owner says it only pulls nearby airborne hairs.

PM2.5 detection is mentioned in both feature walkthroughs and one negative dust comparison. The strongest complaint says another purifier detected 2.5-micron dust while this Shark still reported perfect air.

PM2.5 monitoring is praised through app data and sensor feature evidence.

Pollen comments are mostly positive, with reviewers using it during seasonal pollen or open-window periods. One negative owner said pollen barely changed the reading before it returned to clean.

Pollen evidence is mixed, with expert/customer positives but one customer saying spring pollen did not improve.

Portability is a quiet plus: several owners describe the unit as light enough to move between rooms or easy to lift when needed. Its larger size keeps portability from being universally effortless.

Portability is repeatedly praised because the unit is light and easy to move.

Power connector feedback appears only in a replacement story where support required cutting the cord. It is a negative service experience rather than a normal fit complaint.

Power use is mixed from limited comments. One Spanish-language owner says it does not use much electricity, while another says to expect a higher electric bill.

Power consumption is acceptable in expert testing but one customer complains it raises the bill.

The pre-filter comes across as thick and substantial in the expert walkthrough. Owners who added extra pre-filter material also saw it as a way to stretch filter life.

Real-time monitoring makes the product feel useful and informative, especially when cooking or when outdoor air changes. Buyers like watching percentages and particle information move as the unit responds.

Real-time monitoring is a major strength, with repeated praise for alerts, app graphs, and color feedback.

Reliability is the biggest concern. Several units stopped working, malfunctioned, or developed sensor failures, even though many others worked well during the review period.

Reliability evidence is negative where customers report odd noises, defects, or quitting use.

Remote control is viewed positively through app and Wi-Fi control evidence.

Replacement handling can resolve a failed unit, but it is not always convenient. One owner had to pay shipping and another waited a week after cutting the cord.

Room coverage works well for many bedrooms, apartments, upstairs rooms, and even larger open areas, but some buyers recommend oversizing the unit for faster turnover. A few felt it could not cover an entire apartment.

Room coverage is best for small rooms; reviewers repeatedly caution against expecting large-room performance.

Safety certification evidence is positive but limited to one expert discussion.

Safety concern is rare but serious: one owner threw away malfunctioning units because they worried about fire hazard. This is not a broad pattern, but it matters for risk-sensitive buyers.

The timer is useful for controlling runtime, with the walkthrough noting a 12-hour maximum. It is a simple scheduling feature rather than full app-based scheduling.

Scheduling is praised in app-focused expert/video reviews.

The HP201 is not tiny, and several buyers describe it as large or bigger than expected. Even so, many still find the size manageable, attractive, or worth it for larger rooms.

Customers and experts like the compact footprint, especially for bedrooms, studios, and unobtrusive placement.

Sleep mode gets direct praise from a bedroom user who liked running it overnight without bright lights. The quiet low-speed operation supports bedroom use for many reviewers.

Sleep mode and bedroom use are reviewed positively because the unit is quiet and can dim lights.

Sleep benefits are meaningful for bedroom users, especially people dealing with allergies, dust, or stuffiness. Several owners say sleep quality improved after using it.

Sleep benefits are strongly positive in the few reviews that mention better sleep or breathing at night.

Smart features are a tradeoff: Clean Sense and auto reactions feel smart to many buyers, but some critics see the feature set as basic or ineffective. Lack of app control is the most concrete limitation.

Smart features are a major strength, especially app control, sensors, and auto behavior.

Smoke performance is generally helpful for cooking smoke, candle smoke, cigarette smoke, and wildfire smoke. It may run hard or take time when the air is heavily contaminated.

Smoke evidence is strong in expert testing and a customer fire-smoke odor account, but one defective-unit review is negative.

Value is strongly tied to whether the unit keeps working. Many buyers say it is worth the price or a great deal, but failures, filter costs, and high upfront price make others regret the purchase.

Value is mixed: many think it is worth buying, while experts and one customer stress high upfront and ownership costs.

VOC evidence is mixed: monitoring and some detection are praised, while experts warn carbon is limited for serious VOC issues.

VOC-like sensing is mixed but useful for odors and vapors: owners mention perfume, cleaning sprays, strong cooking smells, and even body odor triggering the unit. One critic says it senses vapors better than actual dust.

Warranty coverage helps, with a two-year warranty mentioned in replacement stories. The downside is that failures just outside coverage can leave buyers feeling unsupported.

Warranty coverage is praised, especially the lifetime warranty tied to OEM filter use.

Wi-Fi feedback is sparse and contradictory to other comments, with one customer praising WiFi connectivity. There is not much detail on stability or setup.