Ok here is my 2 cents worth. I have lived over 50 years in Northern Ill. and drove my 2003 Cummins in subzero temps and never had an issue with the cold weather. I drove that truck in Fla. and around the country in the mountains, hills and flats with no issue. I now own a 2012 Cummins and live in sunny flat SW Fla. I have driven this truck the same as the first. Both trucks were daily drivers and I use them for short trips of two or three miles and also long trips. I have owned gas trucks also. As far as a tow veh. the diesel is the by far a better tow veh. Before you buy consider what size trailer you have and where you want to end up. With the diesel you won't have to worry about not having "not enough truck". I change my oil at shorter intervals as I beleive that is the cheapest form of prevent maint. The only expenses on my 03 that had a 137,000 on it when I traded it was 2 new batteries, brakes and tires all normal issues on any veh. The hemi will serve you well also but you will be restricted on the towing end. Someday you may want to take that 15K fiver up a mountain it is then you will see a difference. Either way good luck.