exercise balls?

[mommyme34]

I have a cheap one that won't stay inflated. I would love some recommendations please. The Xtrain series has some, i wonder if those stay inflated or if someone always pumps them up before use,thanx

 

[bonjonbart]

I have a Gymnic 65cm ball that I got in Physical Therapy eleven years ago. I think I've pumped it up only 6 or 7 times in those 11 years.

I know it was pricey, in comparison, but the PT swore by them. I use mine at least twice a week.