Just bought it and apart from not running with afterburner it's quite fun and hEps mh toping
The first 2 typing of the dead games based on house of the dead 1 and 2 are fantastic and well worth buying.
I bought overkill on steam and wish I didn't, it's got quite lengthy load times even on a decent spec machine and it seems to have loads of swearing just for the sake of having swearing, it's quite embarrasing to play.
For practising typing I think typeracer is better. Plus its free and nothing to even install!