Cold case radiator?

[Tregrad]

I bought one (aluminum "coldcase" radiator) for my 72 Blazer a few years back and it developed a leak, did get hot a couple times but not WAY hot. calle them and they abruptly sent me a new one free of charge! Thought that was pretty cool. I put the new one in and ran it for a bit before going to Kansas to remodel a house. long story short, ive been driving it for about 3-4 months off and on and its leaking again!!! just did a pressure test and its done.
I have 2 - 12 inch fans that are run by my dakota digital electronics. I has barely got to 190 just a couple of times, I set my fans to go on at 170. Im not about to put stop leak in it so does anyone know where to get a STRONG radiator because apparently these are $#|T

[Tregrad]

Ok, I just got off the phone with Coldcase and they have a lifetime warranty on their stuff, cool. They are sending me a new one again, free of charge! The dude at cold case mentioned that there could be combustion in the coolant? Ive personally never heard of that until now, he said that you wouldnt have the tell tell sign of a bad head gasket of water in the exhaust but rather the combustion would be building up so high in the radiator that it would blow the hoses off or ruin the radiator.
That said, isnt that what the cap is for? to let the pressure out when it builds up? Im confused.