Other players, myself included, feel that it's a piss-poor Deus Ex too.
If bugs and performance were the only issue, I'd just have left the game until I got my next-gen console. I asked for a refund because it's a bad game in many other ways too.
YMMV, of course. I hear the story is good and the graphics are definitely pretty. But I'd definitely not describe the game as a 'good' Deus Ex style game.
Funny, I didn't want to buy it before, but now that you say this, I might actually buy this thing. I never found RDR/GTA style games very fun other than 15 minutes of mayhem at your friend's house. Whereas the Deus Ex games are a masterpiece.