I am a penholder who is trying to learn RPB, but learning RPB using Ma Lin's grip is really difficult so I switched to Wang Hao's Grip. Usually penholders have a 2-3 cm gap between the handle and the rubber so they have room for their index finger and thumb. Wang Hao's rubber is straight up against the handle, so his index finger wraps around the handle right above the rubber and his thumb is on the rubber parallel to the blade. Now I have been playing like this for the past 2 weeks, and since I am so used to TPB, when I am in a game I use it a lot. But now my joint on my index finger is hurting a lot, is there any other grip that is good for RPB and is comfortable?