Dunno. don't have an espresso machine but thweaw work for me. A scoop to fill one of 'em and drop it in the machine. Then, after it's brewed, open it, turn it over, tap it out into a contaier (or the garbage, whichever you prefer to not recycle), rinse it out, and I'm ready to go again. Total labor involved (not counting grinding) is maybe 60 - 90 seconds. But, since they come in a four pack I could always fill four at a clip and save even more time.
Plus, I've still got the option of going for any of the liererally hundreds of flavors available in those little plastic cups.