I've owned one of the AMPAC 6-ball rollers for about four years now. In those four years, I've had one problem. One of the rivets, that hold the handle on the bag, broke off. I was able to fix on my own, so no big deal.
One of the good things about the bag is that it holds allot of stuff. Along with a place for six bowling balls, there is at least eight different size pockets to hold everything from your bowling shoes to files and bevels.
One of the things that I don't like is that it is very bulky to pick up and load into car, so for me it is strictly a tournament ball bag. It also has really small wheels, so going over curbs and door stops is sometimes tricky, but, it is easier than trying to carry three, two-ball bags.
I also feel that the whole handle structure is a little on the weak side, but, up to this point, I've only had the rivet problem, so it must not be too bad.
Hope this helps. Leave message if you have further questions.