i've just had a go with playclaw, and really wasnt impressed when comparing it to the MSI afterburner beta. the only place where playclaw is better is when recording full screen at 60FPS, but it used up so much of my processing power that i was put down to a crippling 25FPS on cars, so it wasnt very smooth atall
i say it was better than MSI afterburner because, while in game i was getting ~45-50FPS, the video seemed to get stuck a lot during playback and the audio kept disappearing and reappearing. i'm 99% sure this wasnt a video player problem and was a problem with MSI afterburner
*edit*
well, it turns out it was a video player issue, because the video runs just fine in quicktime player, but not with realplayer or windows media player.
so, that means MSI afterburner beta can record higher quality video with FAR less resources used.