At one time or another, I've had Ultimate, Russell, Corbin, stock (of course), and half a dozen others, and, except for my BMW K12, I have always returned to the Corbin. I had Corbin seats on my Valkyries, Magna, V-rods, RS, and (now) RT - after a bit of break in, I've never regretted the purchase.
But I am a BIG guy - 6'4", and was 330# (now 270, and moving in the right direction).
The Russell was my only choice for my BMW, because of the design I needed to have implemented - the K12 was, by far and away, the most comfortable bike I have ever owned, but many folks can't put their feet flat on the ground when they ride them - not an issue with the Spyder.
I have the new Corbin with the Lamonster cut on my RT, and couldn't think of a better combo. Having said that, I am not 5'8" and 160#……..