Its insanely fun. My suggestion is to do what I did... Before you know how to do anything, make sure you buy a rocket launcher. That way, when you are trying to catch a ride in Zer0's car, you can accidentally blow you both to smithereens. Or, trying to follow Beret into a store, you can accidentally punch him in the head, knocking him to the ground. And dont forget the map... the online playground is very, very large.
Oh yeah, Megs might just run you off the road, and then you spend the next few minutes trying to chase her down, but you wont be able to, so you then just take it out on all the pedestrians. The most fun I had was running over all the sunbathers on the beach. I was laughing so hard, I had tears running down my face. A fast track to 4 stars as well