I've ridden the Gatorskins and the GP 4000s. I find the Gators to be stiffer and not quite as responsive when making demanding turns. I've not experienced any difference in terms of flat protection.
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A conclusion is the place where you got tired of thinking. - S. Wright
Favorite rides in the stable: Indy Fab CJ Ti - Colnago MXL - S-Works Roubaix - Habanero Team Issue - Jamis Eclipse carbon/831