Building a Better Wheelchair

Control is also on the top of the list, it can't be a 2-speed; 1st speed is stop and 2nd speed being "OH CRAP, SO FAST MY EYES R BLEEDING! My powerchair has such fine-tuned control that i leave it on it's full power setting all the time. I can creep, go full-tilt,and everything in between all on the full power setting.