Just a heads up that the rad cap pressure seems to vary year on year, model by model; possibly what MMC had in the parts bin ...
Mine were both 16 psi by Tre (now changed to Stent). Seeing a car in build at the factory with a higher pressure cap caused me to ask if both of mine at 16 psi were correct, the answer was "yes".
I've never had a radiator issue. It would be interesting to know whether CX Mogs with high(er) pressure rad caps have experienced more rad failures than those with low(er) pressure rad caps.