Muntz.
I don't have the Ultimate, but do have the Mustang wide tourer w/ back rest. I have sat on the ultimate though. It is comfortable, and I found that you sit in a little more of a pocket. I went with the Mustang, mainly because it is water proof. I am needing to get my stem bearings changed, so won't be making any long trips until after Monday next week. I am certainly glad to meet up if you would like to see the Mustang.
I agree, that is a lot of Duckies to spit out with out testing.
Just personal taste, I never did like the way the Corbin felt, or looked.
JMO though.