I was in the exact same boat in June of last year. I wanted to trade my 2005 Jeep Grand Cherokee limited that was getting 12mpg. I too wanted a bed to haul my dirt bike (so i didn't have to get a trailer). I was weighing the gas vs diesel options and all the points stated above are valid. After a while, I set my sights on a 5.9 vs 6.7 cummins because I didn't want all the emission components and the 5.9 has been proven itself over the new 6.7. Then I wanted between years 2006 and 2007 (the first half of 2007 was 5.9's, the last half was 6.7's).

I know that the diesel will get better gas mileage, I can haul most anything, It will last longer, it will retain it's value, I've not heard of (and now experienced) any major issues, and the 5.9 only requires regular maintenance just like any other car (however it does require more oil). This is my DD too. In summer I get around 23-25 mpg (half city/half highway) and in the winter I'm around 20-22 mpg due to the cold and it not being able to warm up fast enough (I work nights and it sits outside and I don't plug the block heater in).

I'm very happy with my truck I don't regret anything. This truck is a blast and I will not be getting another truck until this dies.