Roadie, no, once up to speed 5th is still low enough to pull most all hwy. hills. Each gear does become slightly taller (takes longer to run up rpms). The only negative (to me) is 1st and 2nd aren't as quick and I like riding 2-up better with the 17T. BUT, the 18T is much better on the highway. I plan to order a 43T rear to try which would be in between stock and 18/42. It might be just enough to not look for 6th and quicken the starts a bit. Speeds above 65 are only about 30% of my driving. If you ride a lot at high speeds you will probably really like the 18/42 - smoother ride, better economy, more top end.
