Thanks for all the advice, everyone!

Quote Originally Posted by Zen View Post
Clipless pedals are intended to provide a more efficient transfer of power.This is particularly helpful when riding at a constant speed or up hills.

Given that the nature of city riding is stop and go, why would you want to do it in clipless pedals?
I want to learn clipless so that I can ride with them on trails - which is also lots of stop and go at times! I really don't like my feet sliding off the pedals when I'm MTBing, and could use the extra power and security from being clipped in. I guess there's no real reason for wanting to do it in the city, except that the only chance I get to ride during the week is my commute, and I had thought it would be easier than learning on the trails! Many of the MTB trails around here also have paved trails nearby, so I guess I'll practice there for a while before I hit the trails.