This is a very good game, mainly because it is a worthwhile game to play... That is free. Games like this aren't normally free to play.
The only thing that bugs me, is there is no obvious FPS limiter.. So i'm getting like 300 fps all the time, and only need like 60.
Even though this game is a bit glitchy, its tons of fun. Before I got my xbox 360 a few years back, this game was my life. lots of stuff to do on it, and its even challenging at some points.