My commuter started out with a Sram 7 speed hub. It was great when my commute was 11 flat miles. But when I moved and had to ride 30 hilly miles I needed to make a change. You see, 1st and 2nd gear on the Sram exhibit so much mechanical friction that climbing anything other than easy grades is miserable. However, I didn't really like the idea of cluttering up an otherwise nice looking bike with a rear cassette and derailleur. So rather than put up with 7 compromised gears I just picked one real quiet, smooth one! So now it's a 42/16 single speed commuter. If it's good for millions of Chinese and East Indians, it 's good for me.