I've bought 2 of those and bin using them since last week
Regarding a previous comment about the diameter. This ball is hardly a 65cm ball. At 50-55cm you'll be wondering if your done pumping the ball since it looks pretty rigid at this point. Altough siting on it, it will be obivious (from a spectator point of view) that you need to pump it a little more... I've stopped pumping arround 61-62cm but i could have pump it all the way to 65cm ....seem rigid enought to me at this point
They've put sand in the ball (witch you would be able to remove if you want to), at first i was kind of finding this annoying, but after getting use to it, its pretty nice....it prevents the ball from moving arround, and since i'm using one of them as a chair, i find this a good idea.
I've received 2 cds, 2 balls, 2 cds, thats easy math. Altough one of them is defect (cyclic redundant). Well actualy, you can easely see on both cds reading layer that they have bin skratch....must have bin the entire production from what it looks like.....so you might not want to count on that....or bother asking them for an other cd...i guess
The pump that comes with it is pretty much only for the ball as i don't see it fit anywhere else even though they said you can use it to pump your bicylcle tire.... but it,s pretty nice though to get a pump with your ball and not having to search for one .... you get also 3 stopper for the ball
So overall, theres a couple of thing that they could improve other than the ball itself.... beside the fact that the ball could be made a little bigger It's a good ball, well made, anti-burst and the texture let you know that it's made from better material than the cheap 10$ ball So i'll give it a 4/5
** A week later, i can tell that the ball is a 65cm ball, probably the fact that for the first few days it did strech and i can pump it to 65cm diameter and have it perfect
MY DOCTOR RECOMMENDED A BALL TO HELP STRENGTHEN MY BACK MUSCLES. THIS BALL WORKS JUST FINE. I JUST SIT ON IT ONCE A DAY FOR 1/2 AN HOUR WHILE I READ AND REPLY TO E MAILS A/O LOOK UP SOMETHING. AS IT IS NOT WEIGHTED YOU REALLY HAVE TO WORK YOUR LEGS AND BACK MUSCLES SO ITS PERFECT.