I think framerate stability matters a little more than actually how MANY you get. Remember movies are recorded and shown on average at a mere 24fps but because there are no framerate dips or increases it's still butter-smooth enough to enjoy the movie and not really notice the framerate at all. Having said all that, most games are either designed and coded for 30 or 60 fps. Sometimes you get hilarious results if you try to increase or decrease the amount of FPS you get due to in-game physics being tied to the framerate. Personally I find 30fps to be absolutely playable and fine.