Of course, my vote is the Corbin...
Corbin Seats - Unboxing and Installation Review
I visited the Corbin Shop in Hollister and had them make a pilotís seat for my NC700X. After riding awhile I went back to Corbinís for a few adjustments. Rode awhile longer and then returned to Corbinís for a third visit. The total time involved with the Corbin visits was over a 5 month period. That did it for me. The seat then fit me like a glove and I rode it comfortably for the rest of my ownership until I sold the bike.
There were no additional charges for my additional visits to Corbinís.
I'm not a gynecologist, "But I'll take a look"!
2014 NC700 DCT
I have a like new Corbin seat that is awesome. Wife loves it. I sold the bike and have the seat for sale for $400 if anyone can use it.
I've had 3 amazing Corbins, including for the NC. Had a Sargent on my BMW once and hated it. I think the Sargent for the NC only includes a matching passenger seat cover.
If we were going to continue any more serious trips on the NC, I would definitely opt to go the full custom route for the passenger.
My Mrs. (5' 3" 105lb) claims the Corbin was about twice as comfortable as the stock seat, but was still not happy on rides over 45 minutes unfortunately - I can't get her on my NC unless we're on the way to a neighborhood brewery...
We measured that the passenger seat was shorter front to back but considerably wider and taller, the latter especially didn't help her reach the passenger pegs as she was already on her tiptoes to reach them.
Food for thought on the Corbin passenger seat: