I'm getting the itch to test drive one as well. Our local Chevy dealer has a few coming but nothing on the lot. I noticed our local GMC dealer had a loaded 2020 3500 SLT on display on the way to work the other day so on my way home when they were closed I swung in to take a look. They look really nice and well thought out, I will look harder in the coming months and hopefully they will have something along the lines of a LT/SLE on the lot.
The one thing that I found surprising is that the diesel 2500's are within a 100# or so of the last generations SRW 3500 GVWR but the rear axle rating is in between the two at 6600#. Based on my last Cat scale readings I could easily get away with a 2020 2500 with lots of room to spare which is nice as the 2500's are much more plentiful it seems.
Dan