I have MLB2k8 and while its not great I assume its the best one out there. Homeruns comes a bit easy (as do over-the-wall catches), runner control isn't the best, but the rest of the game is pretty solid. My biggest gripe with it though is the lack of internet play or roster updates, which seem like they should be standard by now.
Other than that I would recommend it. Too bad there no turning to throw different pitches, its still the joystick selection like most other baseball games.
