My Duramax has 310,000 miles on it without any problems. Most dependable vehicle that I've ever owned. Took it on a long trip last week and did great and most of it at 80mph.
Read all of this and you will see every body loves their Chebbie, Fordge, or Fiat-Ram.
My neighbor has always owned diesels with mixed luck. He just bought a 3/4 ton GMC and opted for the 6.2 gas. Vehicle was cheaper and so was the fuel. He tows an animal trailer and is very happy with the towing ability. At this time he will not go back to a diesel.