I've done research on these two companies as well. I remember reading on a forum somewhere that Steve Nolen use to be partners with the owner of Cadillac Cookers but they had a falling out. I noticed that PB used pictures taken from Nolen's web page.
Nolen's get support from LuLu's Barbecue (https://www.facebook.com/LuLusBarBque?fref=ts
) so you may want to ask them for some info on the performance of his products. I did and they raved about the quality. The one thing that is annoying me is neither Lulu's or Nolen can't explain to me how the technology on their cookers work.
Cadillac Cookers does a good job discussing the technology behind their cookers. Their customer service is a lot better too (Nolen is very slow at getting back to you). They don't have a insulated smoker but I have been told they are working on a prototype.