In the spirit of the previous posts about finding the right cup, I think we should add a "smoothness" rating for people who are sensitive to things like ridges or writing on the outside, maybe sort of like the size charts.  It might be hard to actually rank them, but I think it would be cool to have all of the information in one place, because it can sometime be hard to tell from the pictures.

I'll start:
The small Lunette has (from top to bottom):
writing:  "Lunette" and "made in Finland"
a small rim, not very pronounced
two measuring lines
three grip ridges
grip ridges on the stem (I'm not sure how many, since I cut most of my stem off)

The small LadyCup/ColorCup has:
no lines or markings except for some grip bumps at the base and on the stem
[I only have the trial one from their promotion a month or two ago, so correct me if the "real" one is different.]

This could also help people who are not looking for smoothness but are looking for measuring lines or grip lines.