Update:

I went to REI, who not only did not have an Ass-O-Meter but had a pretty poor selection of saddles. I purchased a Selle-Royal-Lookin Saddle this one because it looked bigger:

http://www.amazon.com/Selle-Royal-Lo.../dp/B004KWMAKM

Didn't know until I checked the website that this thing is 159 mm! Only had time for a quick 5 mile ride this morning on it, and it was MUCH better. My butt has "normal" soreness I would expect, but it is fine. I am thinking this saddle is probably too bulky, however, for when I go on longer rides. Luckily I can just return it since I got it at REI. I think I need to try a 143 mm saddle and compare, so I can see if I need a 143 or a 155...