Yesterday I got a new 2012 Stumpjumper FSR 29er and I took it to New Melones today for a shake down ride. I'm not a weight weenie so I never considered carbon wheels. But last summer Kip told me I'd gain a few gears on the low end due to lower rolling resistance. As soon as I got the bike on the trail I realized he was right! I gained about three gears. Pedaling is so smooth and almost effortless. The new bike is 5 lbs. lighter than my SJ Expert, but it rides like it weighs half as much. My left thumb is still sprained from my big fall in Tahoe last July and shifting with it is still painful. So I've barley used the big ring since. Today I used the big ring for all but the one mile climb at the end of the ride. Without trying I took more than 20 minutes off my last 27 mile ride there. This bike is going extend the life of my knees. Cell phone photo.