Here's what I've tested, in order of aeroness, IMHO
1. Assos chronosuit - snug w/ thumb holds, zipper does not bunch up, chest tight, go 1 size smaller, well made and durable
2. Castelli body paint - construction looks fragile, zipper area bunched up a little
3. Hincapie signature - used this for the past 2 years, fit well and was durable
4. Voler - went 1 size smaller, fit was ok, not really a super aero solution
Gary, did you test the CS Speed Suit? if so, where did it fall on your list?