Not to get political here, but really I would feel better about buying a new Toyota than Chevy any day. Mainly, they just do not offer a diesel. I know many people with newer toyota's, they are alot nicer, and have way more power than chevy trucks. Toyota probably produces more parts here than Chevy too.
Besides that, I HATE!!!! the Chevy fuel management system. That alone would make it impossible for me to chose a chevy truck.
Go test drive a new chevy 1500, then go try a tundra! Ive driven both extensively, and the Toy wins in every category. After that, check out the resale values of both. Then you'll be sold if you're not a brand name nut swinger.
That being said, I drive a duramax. I feel confident that if toyota made a diesel, this would be Hino diesel forum, and we would be talking about how crappy the duramax is. just IMHO