Yep I've considered that in the past. That's what I bought the balance ball for was to use part-time for sitting to strengthen my back. I think you'd get much better core exercise from the balance ball that rolls and you have to work to keep steady than you would from the chair. BUT my back needs a backrest sometimes so may be nice to have the chair.
Oh BTW my 1st night with the ball took a tumble and crashed HARD!
Scared the crap out of my cats!!!
