As the perfectionist-OCD I am, I'd say I like neither because both have flaws but still like Trophies a little better.
Bad thing about Trophies is that not all games originally had them, and they kind of feel like a ripoff of the Achievement system. I can't accept the fact developer as huge as Namco never patched Soul Calibur IV. I regret putting my money on this game with no Trophies, I should have gotten it on the 360 or not bought it at all (it isn't that great anyway). It's a shame because even a smaller company like NipponIchi patched Disgaea 3 (AWESOME GAME) with Trophies over a year after its original release without Trophies.
Cool thing about Trophies is the level system and Platinum to tell which games are 100%.
Achievements feel like an overall more polished system but I don't like stuff like 1250/1000, etc.
