LT motors with AFM/DFM scare me. Most of my friends with them have a bad experience to share. I had a Yukon AT4 on order for months, but those months gave me too much time to research the unfixable problems of that technology. For many, you'll never have a problem with the motor. And if that's the case, the GM is better looking with better features. One recommendation - do your homework on the engine oil. Put the right stuff in it often, especially during those first 10K. You must use Dexos 1 Gen 2 rated oils. In fact, there's a Gen 3 available now that's supposed to be better. This site describes things pretty well:
https://www.blauparts.com/blog/chevrolet-motor-oil-types.html
What they don't come out and say is that they're trying to keep the lifters from annihilating the engine. The Fords have their problems also, but to each their own. Good luck.