bikingshearer 

I have a San Marco Rolls on all my bike (most are Titanios) because I find them comfortable. I also think they look great. I have done some riding on an old Brooks Pro and liked it, too. I once rode a Selle Italia Flite and it worked for me, too. A couple friends loved their San Marco Regals. but they have a flatter profile than the Rolls that I don't care for.

Everybody's butt is different, and one person's little bit o' heaven is another person's medieval torture device. I have yet to hear of a reliable way to measure something and get a reliable predictor of saddle comfort. This is, unfortunately, largely a trial-and-error thing. And when you find one that works for you, buy a lifetime supply because a corollary of Murphy's Law holds that the supply of any classic bike part you like will completely dry up as if by magic precisely when you need to replace it.