Originally Posted by non-fixie

Not the most dramatic, but certainly the most surprising for me was the steel cottered crank set. The first time I did not immediately replace it with something lighter, but kept it just because this particular Stronglight example looked so nice, I was pleasantly surprised by the smoothness it added to the feel of the bike. Tried it on another bike and had the same experience. I guess the downside is the bigger mass of the thing, but in this pancake-flat country that is not much of an issue.