I just wanted to follow-up to my original 50+ posting:
My bike came with 143 mm wide, medium padded, pear shaped, OEM saddle. I had been professionally fit upon purchasing the bike by my LBS. I had spent about 8 hours on the bike (multiple short <1 hour rides) and was enjoying the bike immensely with the exception of a numb perineum post-ride that lasted for hours. I called my LBS to ask if I should tough it out because I had been off a bike for so long, and I was told a resounding "no" and to discontinue riding until I saw them first. I made an appointment with the bike fitter again.
They put me and my bike back onto the trainer and had me get on and pedal with my hands both up and down on the drops while he looked at me from a number of angles. After reading on the Internet, I was expecting them to measure my sit bone width with some form of butt gage, but they did not. They told me that while academically interesting, they were more interested in see how my pelvis and back rotated on the saddle and my subjective impressions of relative comfort.
My LBS, fortunately is a well stocked Selle SMP dealer and has been fitting them for a number of years. After observing me, my fitter suggested that I try the Drakon, Dynamic, Glider and Lite209 models. What was interesting was while they all looked fairly similar, they all felt different. The differences between some was more subtle but between some and between others were more dramatic. My fitter also dropped the nose a few degrees on each of them which also changed the feel. He also raised my seat post to compensate for the concave saddle profile after observing changes to my leg extension with the cranks.
After 90 minutes of back and forth, I decided upon a Dynamic which surprised me in that it was among the narrower and least padded models that I evaluated. It just was the most comfortable. I think that when I am on the bike, even on the upper bar, in a somewhat upright position with my back angled forward about 45 degrees; my pelvis is rotated forward so the load onto the saddle isn't just on my ischial tuberosities but also on my ischiopubic ramus which taper inward.
The differences between the models is subtle in the geometry and level of padding adjacent to either side of the center cut out, particularly toward the rear of the saddle (say the first 50 mm along the cutout and 50 mm from the cutout to the rear of the saddle).
So far, I have put a few 1 hour rides on the new saddle with no post ride numbness. It is way too soon to to declare victory, but I am hopeful. I was again, amazed at the level of expertise and service afforded me by my LBS.
I just wanted to share my story. Saddle issues seem so common.