I suggest to people that they drive both. I point out some differences in how they feel. I have not driven a 2021 or 2022: just both of in a 2018, 2019, and 2020.
When I drove the 2018 68RFE setup it was slower to get the memo the throttle had "hit the floor" and get moving from a dead stop or at 65 MPH. Coming from a tuned 2003 with a NV5600 "Dump The Clutch" and we are moving NQA. The HO Aisin was quicker to get the memo and get moving, but, a hard sell as it's is also slow to get accelerating from a stop or at 65 MPH. Once they do get them memo, find the proper gear, spool the turbo, etc. yeah they move out quickly.
The HO Aisin is closer to a Manual Trans and the only reason I got a new RAM vs. looking elsewhere.
The 2020's I drove will slip the tires on takeoff so RAM has improved this sluggish throttle response for both transmissions. When I get a loaner vehicle I do a accidental burnout because the throttle is that much more responsive than my 2018.
The 2018 HO Aisin has some refinement needed. The 1-2 spread is very wide and appears to be difficult to handle. RAM doesn't want to drop the dammed thing into 1st gear and leave it there under some conditions. I have had cargo shift from a stop as it decided to bang-shift into second as we got going from a complete stop. A steep grade like a driveway that makes a HO engine reach for first gear is 2 - neutral REV UP - 1st "posi traction test" on concrete. (I limit the amount of throttle during this shift and avoid a burnout. Aka I drive around it. 2019's also have this problem.) The other shifting problems it had have mostly been addressed with software updates. The current irritation is in a slow parking lot where the dammed thing should simply stay in 1st gear and about the time you let off mild throttle it bangs into 2nd gear. Coming to a stop and then backing up can bang shifting from "D" to "N" from time to time as it's wound up with some power still left wanting to go forward.
I have scattered enough transmissions behind diesel engines so I will take the better odds of a MD transmission going the distance. The sound of the overdrive gears eating debris like a muffler blowing up and then dragging on the road gets $$$$ OLD $$$$ quick. Because after all it's only odds... With the number of light duty diesels I have blown up, well, this is why I am driving an industrial Cummins in a RAM wrapper in the first place.
X2 on the Air Ride and 50 Gal tank option. The 5th wheel hitch prep may also be of interest. Cab running lights are no longer standard so if you want those (water leaks) you need to check that box as well. I would make the dealer remove the Firestone tires and put something better on.