I think what Cummins12v is saying is that EGR function and regenerations are significantly reduced with the introduction of DEF to the Cummins in 2013. I am going on 16k kms (10k miles) in mine and I only noticed 1 regen last winter when I wasn't towing and using the truck for more short trips than I normally would. The only way I could tell is that the fuel economy went down and I noticed the exhaust cooling off (ticking) much more when I parked it in my garage. The truck did not perform or run any differently than normal and I would hazard a guess that most people don't even notice when they are in regen.
I can tell you that my truck has virtually no smell when I start it in my garage, much less so than my wife's gas Acura MDX. The new diesels run so clean it is amazing.
My 2 cents worth to you; given that you are looking to keep your truck for a very long time (such as me) I think buying the Cummins over the Hemi is a no brainer. You will enjoy much better towing performance and better fuel economy both solo and towing. The new SRW Cummins are presenting some pretty impressive fuel economy figures. The truck will also be much more desirable at resale time and will fetch you a lot more $ than the gas truck will, which offsets much of the initial cost. Again, just my opinion!
Given, I tow much heavier than you but the Cummins pulls so effortlessly it is really hard to describe until you have experienced it! I usually also prefer to take the truck over the SUV almost everywhere, even short trips, because it is so much fun to drive. Don't forget about the added bonus of the exhaust brake which also works amazingly well. I used to feel a bit nervous about towing in the mountains because of descending mountain grades, and it no longer bothers me in the least now and am towing much heavier than I was with my past trucks. Needless to say I am a happy camper! :B
