I found one at a yard sale, not too expensive, bought it, tried it and I like it. I use it with an adjustable office chair that is petty good also. It gives me some relief from sitting too long. I suspect it is a love it or hate it thing. If you could try one somehow before buying it might make you more confidant or get it from someplace that takes returns if you don't like it.

I have one and used it for a while and liked it...It definitely works your core muscles. My only problem is when I sew, I don't sit for long periods, I'm up and down a lot and it does get annoying to keep climbing up on and re-adjusting. If I have to sit for a long time, I get it out for sure.

If you gave your to Good Will, then I have it! I use it and don't mind it. Fortunately I have no back issues, so can't attest to that.

I'm an exercise physiologist who specialized in Fall Prevention (balance and mobility). We use dynadiscs, (expensive version) in our FallProof class extensively. I bought one for my 95 year old mother and suggested she use it while she eats breakfast. I don't think I would recommend sitting on one of these for many hours. OUr classes run for 1 hour and we do many things in the class besides exercising while we are on the dyna disc.

More importantly than this piece of equipment is to set your chair and table height correctly. If you do use one of these for part of the time make sure you adjust your chair to the correct height. I would use the disc for a limited amount of time and build up. I sit on the smooth side, although my mom likes the other side. I'm going to try it while I'm sewing today and see if it helps.

I use it whenever I sit and sew. It keeps me balanced and no sore back. It is a must have for me. My young grandsons think it's fun. It's durable!

My PT says--do not sit for more than one hour at a time. Make sure you are getting up and walking around. I know how tempting it is to keep going with a marathon sewing session but old bones and joints don't like that!

I have used a balance ball at my computer for about a year now and I absolutely LOVE what it's done for my lower back! It honestly has made a big difference. Plus it's fun to bounce around on when I'm listening to music. However, I find that I'm making my mousing wrist VERY sore by pressing on that arm as a means of maintaining my balance, and it's a habit I can't seem to break. I have tendon problems in my wrists already from typing for a living, and I need to be careful with that as I can't retire yet! So I have reluctantly bought myself a standard office chair and I plan on putting a Gypsy sit-upon on my Christmas list so I can get back some of that "wobble and bounce" that I've enjoyed so much from my ball, and hopefully keep my back feeling this good.

I think I'll plunk the ball in front of the TV instead. Who knows, maybe I'll even work out a bit! (Nahhhh)

I had the mouse problem til I put a square of thin wood on my lap and used a wireless micro-mouse on it.