I have a KR 4-ball roller, and for the most part I like it pretty well. The only real problem for me is that it sucks having to take it down to put in the back of my truck, especially if it's raining. Also I have the older style bag which not only has the small inline skate wheels on it, but the lower section is top loading which almost negates the benefits of have a 4-ball bag due to having to take the top off to get to the rest of my equipment. A friend of mine has a new KR 6-ball roller which I must say is very nice, and great when we go to tournaments(only real time we use it.) All of the compartments on it a front loading which is a major plus, and it also has the large wheels making it a bit easier to roll, however it can be a big pain in the @$$ to navigate just due to the sheer size of it...
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