I'm totally tempted as well due to the 8spd tranny. I really don't care about styling and whatnot but the tranny in my 2014 pretty much sucks donkey balls when towing heavy.
I agree but let's face it, you can maintain the RFE yourself more easily than the 8-speed box now behind the 6.4. Cold comfort, you may say, but it's also been around so long the mods for improved performance are available, too. Still, one thing the older tranny will never have is better fuel efficiency than the 8-speed and with a thirsty 6.4 in front of it, that's something.
As for me, I've took both new '18 and '19 2500s with 6.4s and I'm still deciding. The older ones are cheaper, of course, and rapidly disappearing from dealer lots. I know the new combo is better, but with clearing our new property and putting a barn and house (yes, in that order) on it will require some funding. Also, I've found it hard to jump into a Tradesman from a Rebel -- which I'd have to do if I were to get a new rig -- as there's something about all this new tech that make driving, well, better.
TXCOMT