Buy the higher end bags when you're looking at 3 or 4 balls, etc. They cost more up front but the frame, handles, wheels, zippers, fabric are all more durable. Over a period of time that's a lot of weight we ask them to bear (which is why we're rolling them instead of carrying them).
I have used the Storm Thunder Roller 3 ball with great results in the past, and have currently used a 4 ball Brunswick Pro Players (made by KR) for four years, and it is still in perfect working order. It's got a five year warranty on anything that might go wrong (handle, wheels, etc,).
charlest brings up a great argument. They are made for a certain price point. Some people don't bowl very often and will be completely satisfied with a bag at a lower price point. But we who bowl constantly, and are taking then in and out of trunks, in and out of bowling centers, up and down stairways... you name it, need to get a heavier frame and components or they just won't handle the abuse.
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Lane Carter, Strike Zone Pro Shops - Salt Lake City, Utah
Brunswick Amateur Staff