Boiler type (single vs dual)

Marketed as having a dual-boiler style setup for the price tier, which is treated as a notable spec advantage for making a range of drinks in a super-automatic.

It uses a single stainless-steel boiler, so it can’t brew and steam at the same time, but the practical wait is short because it switches from steaming to pulling the shot within seconds.

Using Breville’s ThermoJet single heating system instead of a dual boiler keeps the Bambino Plus compact and quick to heat but limits fine grained temperature control, so serious espresso purists may still prefer larger and more expensive dual boiler machines even though the ThermoJet setup is more than adequate for most home users.

The heating approach prioritizes rapid water heating, but cold-start temperature stability can suffer because the grouphead and portafilter aren’t warmed automatically, making a preheat routine important for avoiding sour, under-extracted shots; the reviewer suggests a quick flush routine to get to brew temperature before the first pull.

The Jet relies on fast ThermoJet heating rather than a true dual-boiler system, so it can’t brew espresso and steam milk simultaneously. In practice, the short wait to steam (around half a minute) is a manageable trade-off for instant heat-up.