Whats the most disappointing game you've bought?

The graphics were shocking but I felt they got the handling pretty much perfect from the arcade!

 

Sonic the Hedgehog, bought together with my PS3.
Disasterous.

 

Saints Row and Star Trek: Legacy for the 360 and WrestleMania 21 for Xbox.

Legacy was delayed several times to not compete with several other games in sales (not that it mattered any) and seems that the PC version got a few more fixes. So many problems getting online.

WrestleMania 21 was just one big pile of buggy crap on a disc. Bugs, glitches, piss poor play, pathetic online play (lag galore!) made it the only game I've ever taken to GameStop for credit in sheer frustration of the game. Studio Gigante should've stuck with fighting games since they were part of the Mortal Kombat team...ironically, the studio no longer exists.

Saints row is a game that was alright at first, but after playing it for a while, the quirks really stand out. The quirks are a hundred-fold worse in multiplayer. Between lag, cheaters (standbyers, glitchers, TKers, etc.), piss poor use of the Havok Engine (physics my ass...since when does gravity become irrelivant for several seconds when you get knocked up in the air?), and Volition Inc.'s lack of caring to fix even some of the remaining problems even with the patch and instead focused on the crap add-ons makes me extremely reluctant to even bother with the upcoming Saints Row 2 (apparently TBA 2008).