I'd say you'll find a noticeable improvement. Not enough to turn you in to Lance Armstrong or anything, but worth it.
Originally Posted by
wfrogge
Some will say clipless allows you to "pull up" but studies have shown that cyclists dont put out much force this way.
Really? I agree under most riding I don't think I gain a lot on the "up", but when climbing (especially when standing) I feel like I'm really pulling up quite hard on the pedals. And the original poster seems to be asking about climbing.