Really one hell of a question: It's one I'm going to get to struggle w/ for quite some time.
Don't have an CVO Ultra but had an 01 Ultra (88) and an 00 SERG, got an 05 SEEG (103) and the 09 SERG3:
Quick version is clearly the Ultra has the amenities over the RG. Lowers, tour pak, seat, saddlebag guards, windscreen, cb are all good things and the RG needs some of them. RG is the best looking bagger out there. Going down the road my money's on the RG. Wind, calm, trucks, freeway, two lane, fast, slow it just doesn't matter. Both EGs I've own(ed) had issues w/ high speeds, sometimes 'cause of the weight (BSR and luggage, sometime because of the speed, but I've yet to have any of that w/ the RGs. BSR clearly needs wind protection so it'll be the dorky windscreen for touring for now. Probably get a Clearview over the winter.
Trip to Milwaukee will be the first long distance test on the new RG but I'll be shocked if I don't get back home just singing its' praises.
Like others have said, having two CVO tourers is just one hell of a thing. Both are frickin great. Both do lots of things really well, go plenty fast enough and always get attention and admiring comments. Guess one can only check them out then go w/ the one that moves their sole.