As much as I love my Nexus system (cp-e), IF I knew about the Thermal at the time, and Ron carried them with his discounts then, I probably would have gone for the Thermal (and yes, changed out the tips for a big turn down).
I would ABSOLUTELY take it over the Cobb, NOT because the Cobb is not a great system, but because it is 2.5", and like The Grouch says above, I want a 3" system that is 'power mod-proof', just in case.