This game is OK. Anybody familiar with GTA can immediately jump in and play. Everything from the controls to the AI (or lack thereof) feels almost identical.
Differences from GTA:
-- The police are much more lenient. I beat like 20 people to death without getting the cops on me. Also, the police will easily give up on chasing you if you manage to get away.
-- Instead of having barriers that kind of make sense like in GTA, there is a glowing, red, transparent force field that keeps you inside your "zone".
-- Driving controls feel a lot tighter and less "floaty".
-- The physics are much more intricate, although not exactly lifelike. I kicked a dead woman in the crotch and the body went flying. It was hilarious.
-- Cars take a lot more damage before blowing up. Although there's the same progression of cosmetic damage->white smoke->black smoke->flames->car explodes.
-- The AI is even dumber. People will patiently sit there while you jack their car or beat up pedestrians 2 feet away.
-- For some reason there's no blood at all. I guess they wanted to keep it family-friendly.