Haven't ridden a 1290 but put 11000 miles on an 1190 which I suspect is similar to the 1290. Yes, you still know you are on a twin. Yes, it still prefers 4k+ on the tach. No, it doesn't buck around and sound like someone shaking a box of rocks under 4k while under load like the 990. The newer ktm twins are better than the 990 mills in every way.
The guy rode a 1090 and 1290 back to back and his thoughts seem to mirror yours. Yes the 1290 was an absolute blast, but he liked the 1090 a lot and didnt in anyway think it a slouch compared to the 1290. He prefered the front end feel and although the electronics of the 1290 meant he "took the piss", he did end up actually crashing it.
How about the 1090-R? Is it just a smaller lighter de-teched 1290 SA-R? I NOT a super hard off-road rider, especially in a heavy adventure machine. I love my 2007 KLX-250S for putting around at ~45MPH on country roads and limited moderate level off-road things. I find I don't ride my KTM 450-XCW much these days KTM 1090 vs 1190 vs 1290 Adventure R. Comparisons between the 1090 Adventure R and the new Honda Africa Twin โ€“ and, for that matter, also with the old 990 โ€“ are inevitable but letโ€™s look at the differences between the new 1090 Adventure R and 1190 Adventure R and 1290 Super Adventure R.
Woody's wheels sells rotor adapters making all 950/990 fronts fit directly on all 1050/1090/1190/1290 adventure models. In fact if you call woodys and order a front wheel, it's the same wheel for either bike model, just the new gen bike owners are supplied a wheel fitted with the adapters. Couldn't be easier. #10. LukasM , Jan 2, 2019.
As for vibrations, yes it does have that Big twin vibration. I had a DL1000 and the DL was smoother but like the 1190 it did not like top gear below 50 mph. Gearing the KTM down one tooth helps and only changes the rpm by about 500 rpm. Not a big deal on a bike that will run 140 with out any problems. . 322 372 20 137 206 75 309 44 67

ktm 1090 vs 1190 vs 1290