The absolute standard for a prosumer is 15-bar pressure; this is the type of pressure you need for a good espresso in the convenience of your own home. In addition to the pressure, you also want to pay attention to features such as temperature control and a milk wand. Those looking for a prosumer tend to expect more from their espresso machine, so features certainly demand more attention for these products. If you want the get the best from your espresso machine, the functionality is in the smaller details.