I recently had a meal at each, the former for the first time in a while, the latter for the first time period. Prezza, IMO, was wholly unimpressive for the price (though I did not try Rubee's arancini and probably should have). Tried the grilled squid and octopus with white beans--the creatures were overcooked, the beans undercooked; also tried the steak tartare, which was fine, but not memorable, hardly the best I've had in town--at present that honor goes to Brasserie Jo (still) and City Bar, where recently I was shocked by its grayness but also shocked by its serious flavor. An accompanying little brick of baked ricotta was wonderful, however.
Copia--I should say that I'm pretty sure chef Caturano was there that night (though I'm pretty sure he was also at Prezza on the other night)--surprised me. An excellent Caesar, one of my primary yardsticks. Everything was good, actually, but the real kicker was brussel sprouts stewed with tomatoes and gratineed--just one of the nicest (not to mention richest) treatments of that particular veggie I've ever come across.
Server was eager, a little overeager, but well-intentioned. (E.g., he proudly took it upon himself to split the Caesar for us b/c my DC hadn't ordered a first course--only we hadn't said we were splitting it, and I was hungry and hadn't planned to! So my DC, who granted is a friend, probably saw my ugly, primitive, snarling side come out at that moment. Since I know she reads the board--hope you forgive me, DC.) Still, I'll take eagerness over other errors any day.