Performance currently has a chain checker on sale for $4.99.
http://www.performancebike.com/bikes..._400005_400140
I use one and found that all chains wear at different rates. I suspect weather conditions, the number of times I clean & lube the chain, and number of hills I climb while standing all have an impact.
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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