On the positive side, capsule-based espresso machines do deliver consistent, good quality coffee at home, better than you would get with a consumer espresso machine using pre-ground coffee that you keep in a vat for a couple of weeks.
On the negative side, I am often disappointed by the quality of espresso in (Italian) coffee shops. It used to be that the quality of coffee was paramount for a coffee shop, and a good barista either learned how to get good coffee quickly or went home; now it seems this is perceived as a much less important part of the trade, and you regularly get restaurant-quality (as in very mediocre) coffee in coffee shops. Not sure if Nespresso played a role in this too, as less people are walking to a shop to get their coffee.