VA,
The GM products I have been driving for the past several years have given me great service. A 1/2 ton extra cab with a 5.3 will be a great choice. Good fuel economy and I have found them to be very reliable.
Just bought a 2012 2500HD LTZ w/Z71 and a 6 Liter. Put a Leer XL100 on it (8' bed) and love it. Rides great, noise level very low, excellent power, great brakes, and very comfortable. Only one issue with this beast but I knew it going in. 14.2 mpg highway and 11.5 mpg around work and town.
Last one was a 2007. Traded it with 91K on it and the truck held good value on trade. Gasoline, tires, and fluids in 5 years.
FWIW I noticed that true 4 door trucks had quit a bit better trade value over an extra cab but I like 8' beds and a four door w/8' bed is a yacht.

Dave