In my limited experience, tube quality is all over the place. Some loose air quickly, some don't. Some come prepunctured, some don't. Unfortunately, I have not seen any correlation to brand. I suspect they are all made in the same crappy factory.
jim
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Cross Check Nexus7, IRO Mark V, Trek 620 Nexus7, Karate Monkey half fat, IRO Model 19 fixed, Amp Research B3, Surly 1x1 half fat fixed, and more...
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SB forever