I have come into possesion of a handful of commercial espresso machines and I seem to notice a common theme in all of those machines. They all are dirty, stink and full of crap in the groupheads, portafilters and boilers. They all had thick accumulation of coffee grounds, chocolate sauce and baked milk all over the place inside the machines. This make me feel disgusted that these machines were actually in service, at one time making drinks for customers who pay a lot of money for these coffee drinks.
This is a serious problem and from these experiences restoring these machines, I have come to the conclusion that I will not order drinks in cafes that I do not absolutely sure about the cleanliness state of their equiptments. I think most coffee consumers should start to look at cafe with critical eyes as well, afterall, the the positive health attributes of coffee will be nullified if people consume coffee made from these dirty machines.
Perhaps some clues we can use to spot bad cafe are:
dirty and clutter appearance of machines
baristas who looks liket they don't care