I have a 2014 2500 and it's been a fantastic truck. I have had all the recalls done, which admittedly is a little annoying but it was all free work so I can't complain really. One recall even included a completely new DPF/DEF catalyst system which had to be really expensive. Again, free so I didn't worry about it.
In 3 years of ownership I have had a check engine light once. It was for an 'Insufficient Catalyst' and occurred not long after I had filled my DEF tank with cheap stuff from a farm store. When I got home from that trip I drained the tank and refilled with Peak Blue DEF and have never had another problem since. Coincidence? Possibly, but the results speak for themselves.
With general, non-towing, driving I can go for months without refilling the DEF tank. The truck uses the fluid very sparingly but DEF consumption definitely goes up when hauling a load. My guess is the '16 has emissions equal to or improved over my '14 so I wouldn't imagine you'll have any problems.