My only complaint so far: I understand you're not supposed to install the "play" disc, except I'm running an older 360. With the active disc not installed, the thing sounds vaguely like a passenger jet taking off in my living room. Is there anything to be done about this, or am I SOL for not buying a newer version of the same console I already own?
Apart from that, it's great so far. I played the first few story missions, then took off to do some sight seeing. I decided to hold up a 7/11 on a whim. In retrospect, an ambulance might not have been the best choice of getaway vehicles.
Speaking of vehicles, they seem a little sturdier this time around. In IV it sometimes seemed like a violent enough sneeze would set them on fire.