While I made sure to get new rings with pins and ramps (Stronglight), I have to say that the ramps aren't nearly as effective as those on the Ultegra ones I took off. Those ramps are huge, and they worked flawlessly. I'm sure Shimano also optimized their pins/ramps to work on their matched ring sizes.

Do other manufacturers of compact-sized rings (like FSA) have matched sets with really good pin/ramp systems? Since I was going with 48/34, which is not the most popular combination, I didn't try to look for a matched set.