man, you make me want to try it out solely because of volition's involvement and me loving the Red Faction series. On the other hand, I'm pissed they spent so much time on Saints Row. lol.
It's a really good game. It's a lot like the RFG style. You've got your main story missions, side missions, open world, challenges to complete, and creative weapons, like the Penetrator, a purple sex toy the size of a baseball bat. So it's a lot like RFG, but with drugs, hookers, and takes place on Earth.