Very frustrating to try to find the specs for EK and especially Endorfy, even on their websites. Honestly, though, none of these brands provide enough info, although Enermax and TR probably did the best.
I couldn't find AF and SP for Endorfy pump and fans, and their fans have the lowest RPM. I couldn't even get dBA. Their fans have MTTF of 100,000 hrs. The pump is probably the slowest, although Azza didn't list the pump RPM (but was the only one to list L/H and mmH2O) so aside from the KGT review, I can't say much.
I got the AF and SP for EK's fans, but not the pump. They have the highest max RPM
Only Enermax (probably) has a copper rad, and also a copper plate. All the others, except Azza, have copper plates and aluminum rads. Azza uses aluminum for both.
The Enermax has the best fans, followed by the TR. Sadly, the Azza and EK fans are pretty similar, with the EK having better CFM and marginally better mmAq - no wonder they put 6 fans on the rad! However, the TR fans are the quietest.
Frankly, it's hard to know which has the best pump because there's less data except for the Azza. However, the Notte has 5300 RPM, which is far stronger than the EK and Endorfy.
So, to me, it seems like the $100 discounted price on the EK is warranted, and the Endorfy should be around the same price. I suspect the Azza is not that great but at least the pump goes up to 3,300 RPM. It seems, then, that the Enermax and the TR are the best options. Since the TR is an unknown at this time, I'm going to go with that unless someone can share some compelling reasons against it and for one of the others.