Why did you not buy the heated Mustang seat for your Ultra? Mustang says there heated touring seat sits 1" lower than stock.
I bought the Mustang gently used for a great price. It's absolutely lower than the stock seat, but still taller than the seat on my '07 Street Glide. And I don't mean distance to the ground, because that's obviously different for an FLHX vs. a FLHT. On the '07 I feel like I'm sitting down in the bike - more a part of the bike. With the frame changes on the '09, even with the lower Mustang seat, I'm sitting on top of the bike.
In addition, the Mustang is nice, but not all that comfortable for longer rides. For me anyway. Some of us have sufficient padding built into our back sides and some have little to none. I've gained weight over the years, but mostly in the gut
so I still basically have no ass, so I sit right on bone.
So, if the 2012 SEUC seat is lower than the 2009 and it's as comfortable as I've heard, it might be worth the $$$$. I'll have to see if I can locate one in a showroom around here for a test sit.