Thanks a lot for the through review, great work.

My personal conclusions for medium to low noise environments are:
the GTX is possibly the best radiator on the market provided that you can fit fans on both sides, achieving a flow rate comparable to an higher fan speed at a lower noise.
Nevertheless, the price premium for such performance is completely unjustified: twice the price for not even a degree less just makes no sense, especially if you can fit an additional (obviously not stacked) rad for a more definite temperature and noise drop, so we can probably consider the MCR the real winner.

Anyway, whenever you got time to spend, a push/pull with optional shrouds analysis would be much appreciated. I'd really enjoy a noise-to-performance chart including all possible combinations.