Sonic used the wheel the moment I put it in. Its one I made myself, since I have no money. I used a ice cream pail, then cut the curled edge off, the filed it down, then I put electricitians tape around it. For grip I used some masking tape and some elastic bandage patch work around the wheel. (I'll get a picture if any one is interested.) I drilled a hole through the center then put a round head screw, and used a small rubberband around the screw so it doesn't make any noise. For the holder I used a clothes hanger (wood). Yeah its cheap but right now staying in the black is good news for me... While building it I looked at many things that could hurt my hedgehog and did some research on some materials that would be cheap but effective, I was just wondering if the wheel can sufice for the time being, it took me about 5hrs to make, and cost $8(canadian). I will try to post some pictures in a bit.