I read in a thread on hear that the grippers will still work if you lift an inside wheel, where as the quaife wont, but the quaife is maintenance free. The gripper needs servicing every x miles. From the way that thread went people seemed to say the gripper was better for more serious usage (which would prob suit the OP and Burp). For track days etc... the quaife seems the better bet, kinda plug and play if you get what I mean.
This is all from what I read, I have no actual experience. I will have a search for the thread now.