This is possibly the best game on the 360, and thats no overstatement. The 'flaws' in this game are far less than whats been mentioned, and most security points remain emptied unless you drive across the other side of the game map and back again!
I was even going to buy a bigger tv just for this game but decided 32inch hd is enough.
Multiplayer is great, some difficulty accepting game invites from friends, im sure it is a temporary thing.
Single player is amazing, multi player even better. I have cod4, gta4, gofw and i play this by far the most