Moved it down here where you'll get replys from those of us that have crossed over.
There isn't anything that compares to an Ultra Classic in the comfort dept. in the HD line up. Having said that, let me share my observation. I've owned several Ultra Classics before the 04 SEEG. The newest UC was the 02 UC.
I learned early on (with my 89 Ultra Classic) that the seat on an Ultra Classic is like a big ol comfortable couch. And it stays that way until about two hours into the ride....from there through the rest of the day, it gets more and more uncomfortable. So I changed the seat on all my Ultra Classics as well as the SEEG and the SESG.
I was one of those guys that had motorcycle seats hanging all over the garage and never satisfied until I tried Vanamal's Corbin. I rode ocean to ocean on that seat and it's not been off since! (I did send him a check

. My new SESG also has a Corbin.
Besides the seat issue, the SEEG and the SESG is the same chassis however, differet suspension. The SESG handles tight compared to an UC......kind of like comparing my BMW sedan to my Silverado truck. It rides a little stiffer, but handles so much better....so you're trading off a little of the cush for a much more sure footed beast.
Like all the models, you have to get a windshield that fits you and your rider.
Stereo.....I bought the HOG Pod for less than $200 and was amazed at the difference at freeway speeds. Don't know if a passenger can hear it any better (I ride solo) but I can honestly hear it at 100 mph now. Of course there's the Hawg Wired system to bump it up even further.
I'm one of those that has added the quick release King Tour pack, the leg fairings, etc. I like the comfort when I'm touring and I do a lot of it in the summer months. The up side is that when I'm riding local I can remove all that and have the sportier looking ride and much less weight. That's my experience.