We drove several '16 Ram 2500 and 3500 SRW Cummins before purchasing our '16 3500 SRW last year. We felt the 2500's coil suspension was noticeably less jarring when driving over very rough RR tracks. Most of the time our 3500 SRW drives just fine; however, under certain road conditions the 3500 SRW's leaf suspension can definitely get your attention. We needed the extra payload the 3500 SRW provided; otherwise, we would have purchased the 2500.
We run our 3500 SRW's rear tires at 45 PSI when empty. It does help, but it's not a magic pill.