Towing comparisons

Depends on configuration for towing capacity, which trans, 2x vs 4X, long bed vs short bed, cab, etc.

Here are some charts to wade through:
2006
http://www.rambodybuilder.com/2006/docs/dr/mlup.pdf

2017
https://www.ramtrucks.com/assets/towing_guide/pdf/2017_ram_2500_towing_charts.pdf

2500 will be less uncomfortable when not towing (I drive a 3500, pretty stiff). I would think the 2017 has a few more creature comforts and less miles?

Have fun whichever way you go!