First ride with another trail, finally! We tried them out in some rough terrain, they both climbed back out like billy goats. Probably close to their practical limits. Mine with the 13 tooth front sprocket made for less downshifting on long uphills. On the flats the 23 might have been a tiny bit faster. The 23 only has a couple hundred miles at the most so if it opens up some after some miles it will be faster on the straights I think. My only regret so far is the lack of other trails to ride with.