Are the frames or seat options different between the RT and RS? Seat size does play into account a LOT. We ride long and hard. I have done 1000 miles a day solo, and 800 two up on the Sporty- BUT....Momma says we will be a lot more relaxed pace these days.
The Tri-glides are out of the question for a few reasons. Mainly, I am not dropping $35K on a bike. Not to mention, its the size of a buick. lol.
As to my pain levels- That is something I work on a daily basis. Some days, I feel on the edge of control, others, in spite of my over 2 doz pain pills a day, its more then I can deal with. (just for clarification- my Dr is VERY involved and in control of what and how often I take for pain)
I am concerned over the arm strength to handle a trike. I rode a tri-glide, and it was indeed a different dynamic in ride, and I found I was using my left arm to "muscle' the bike and my right arm to run the throttle. I am fighting the sinking feeling that I may have damaged my arm beyond motorcycles now. Its a major risk riding 2 wheels, as if I ever HAD to catch the bike, or leaned it too far, my right arm would give out, ripping up the rebuild and it would be non-repairable. Yet 3 wheels, in any configuration seems to require more arm strength then I can muster.
I will find a local dealer and go try out a spyder. Not giving up just yet!

Thank you for the kind and informative responses so far.