Back when I painted conversion vans @ Winnebago we used Dupont. When I owned my own body shop I used PPG / Ditzler. Never had any "product quality" problems with either. I've been told by several body shop guys to use House of Color when I get the "Z" ready.
Any of these, Martin Senour included, are quality products, it's more a question personal preference than quality differences. Using compatible products from start to finish would be more critical than brand name I would say.
But then that's like saying Chevy Ford and Chrysler are all quality products. There's always gonna' be diehards out there that will swear by one brand or another.