As far as quality of components and build quality I don't think you can beat macs as a box stock computer, but comparing a built gaming computer to a stock MAC is apples and oranges
I dont think you can go wrong with a 5.3 or 6 liter ls based motor. They take a beating and keep on going.from my experience. Sbc will always be an easy go fast but I think the ls platform is a sweet motor with tons of potential!