I'm giving this three starts because when I leaned back to reach for something, it tipped back, and then slid out from under me. I fell hard on my back. It was my fault, because I think the wheels got caught on my purse strap, but I'm including this as a caution for future buyers. Otherwise the chair has been great for my posture and for sitting all day during my third trimester.
this chair makes it so much easier not to cross my legs and keep my back straight. I may look a little "funny" sitting on my ball but this is so much more comfortable. Especially when I have to sit for long periods of time doing my computer work, I can bounce a little, rock a little, and move around without any trouble at all. So far the ball is strong and sturdy. I can roll it along the floor pretty easily. The chair itself is very light weight and easy to move out of the way or to another location.
I have been eyeing this chair for years. I finally made the purchase and I am so glad I did. The office where it's located is a small room, so first I was happy to get rid of the big bulky office chair I've been using. Secondly, it's a nice change to sit at my desk in this sleek, easy to use chair that forces you to sit up straight and use your core muscles to balance. The only thing I don't like is having to inflate the ball at least once a week, depending on how often you sit on it. The inclusion of the balance ball chair system guide is a nice bonus to getting more value out of this therapeutic chair. Overall, I am so glad I made the purchase, so worth the wait!