I have the KR 4 ball roller bag. It has been in constant use for 4 years with zero problems. Bottom bag opens from the front (only sensible method), lots of extra little compartments. Easily separates into two pieces to store in a trunk. Or, in my case, makes it easy for an old man to put the two pieces into the back end of my Jeep. Takes lots of abuse and keeps on working.
Now, if I could only get it to knock down more pins!!
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Never take a sleeping pill and a laxative on the same night.