I'll say this again. Seats are very subjective. Only YOUR butt knows whats best for you. I loved my Corbin seat on my Vulcan. I love the Corbin seat I put on my FJR. Some people hate the Corbin seat. Ten years of being on the Vulcan forum has shown me that the folks that like the Corbin tend to be small of stature and with little uh, natural padding back there.
Folks that are let's just say heavier, with a bit more natural padding, tend to
like the Mustang seat. The Corbin seat is very firm with less "Cush" than the Mustang. You'd think the preference would be the other way around, but from
my observation over the years, not.
Not writ in stone of course, just what I've seen. If you have sat on Vulcan with a Mustang seat and really liked it, there you go.
Price wise, for you, I'd go for a Spencer redo of the stock seat and then go from there.