Factory hydraulic roller lifters that work... LS for the win!
Seriously, it's hard to overlook the performance capabilities, and the features built in from the factory. Many already mentioned.
I think the answer, as usual in comparisons, is "it depends".
A friend I work with has a 99 or 00 Camaro. Still has the original cathedral port LS1 heads, intake etc. As a retirement gift to himself he had a 402 built and used the aforementioned original (but ported) heads, intake etc. Made (N/A) 620hp on the dyno, is driven to the track and runs 10.20's @128+. Just imagine building a 400ci Pontiac that makes 620HP, and what it be like to drive, maintain, etc.
Brand loyalty is cool, and I get it. But GM, as they well should have with 35 years more experience and all the technological advances that occurred in that time frame built a better mousetrap, no pun intended.