My last 4 Trucks have been diesels.
2002 ford 7.3
2004 ford 6.0
2002 chevy 6.6 LB7
2005 chevy LLY
I just purchased a brand new 2013 chevy 2500HD with the 6.0. This is my first gas and I can tell you I'm not going back to a diesel. If your not towing alot I would stick with a gas over a diesel. I tow almost the max, which is 20,000 and I feel the 6.0 motor with 4:10 does fine. I do feel the duramax is a better engine over the ford powerstroke I've had in the past. I have had less problems with my duramax over my fords. Im just going to give you my opinion based on real world experience with the newer ford diesel. I work for a contractor that deals with natural gas pipe lines. The trucks we use are ford F250-450. They are not taken care of by the drivers and they run all the time. Anyways last year they order 32 new trucks with the 6.7 to replace some aged 7.3 and 6.0. Out of the 32, 14 had blown motors and 8 had blown transmission to date. I do remember them talking about some issues with glow plugs breaking of and falling into the engine, but im not sure if thats what cause the engines to blow up. Im not comparing brands as we don't use chevy or ram so I have no clue how they would hold up in that kind of environment. Im just giving you some info from my experience with the newer 6.7.