I'm back from my trip to the Southwest. My father-in-law and I both rented R1200RT's and rode for 5 days, with our wives as pillions. We had an open agenda and based on weather, decided to leave from Phoenix and head northwest, spending nights in Kingman, Vegas, Lake Havasu, and finally Sedona, before returning the bikes.
I think the bikes we had were each equipped with BMW's low seat option (and it's vexing that the rental company couldn't tell me specifically whether that was or wasn't the case). As a result, I felt rather stuffed into the leg position after the first few hours of riding. I'm 6' tall with a 32" inseam and came to really dislike the leg position even as I appreciated that the overall geometry was perfect for my back and upper body. I just really didn't like the stiff knees I had the last 3 days of the trip that caused me to need to stop every hour to stretch out and walk around. I missed my CTX every minute the last few days.
My other complaint on the R1200RT would be the power at low speeds. It's like 1st gear is just too tall or there's not enough torque between 1000 and 2000 rpm for the bike to get moving, especially uphill. The CTX practically launches itself forward just based on letting the clutch out, and the RT only launches itself forward with a lot of babying on the throttle. I only stalled it once, but this irritated me the whole trip. Especially considering the bike has a crap ton of power up top. Which leads to the positives.
The power at speed is basically perfect and wonderful. I've never felt a bike that just kind of goes exactly as you'd want based on a twist of the grip. Very confidence-inspiring, great for the highway. A little smoother and perkier than the CTX.
The balance, even with a pillion, is just about perfect. Except for when going at less than 5mph in parking lots, where the height works against you and it kind of wants to flop about. But otherwise riding this bike with a passenger felt like riding a lot of other bikes solo. Slightly better than the CTX, which is also good here.
Wind protection was perfect. I loved the adjustable windshield, which worked well in concert with my Shoei full-face to give me either full protection or lots of air flow when hot. Wish the CTX had something like this adjustable shield setup.
I got tired of the noise and slight vibration of the boxer engine by the end. That coupled with the lightness of the bike, which otherwise would have been a positive, made it feel somehow more fragile and loud and junky than I think the CTX does.
And with that as my final impression, combined with the stiff knees, I was happy to turn this thing in, and happy that when I bought my CTX I didn't seriously consider dropping a significantly larger amount of money on the RT.