The only thing that bothers me about things like this is you will probably wear out the keys it uses as I don't know you, but I hit joypad buttons far harder than I would my N900 keyboard.

I really wish there was a bigger market for dockable joypads as that for me would be better, as it it could contain a proper pad design and make holding the N900 for gaming more comfortable. Although I have to admit, the Gripper is more pocketable.