Didn't we just put this topic to rest recently?
It's yet another arbitrary "best of" list with no supporting data, only a mention of a few key features. 7x-500 has a high-pass sidechain filter and a wet/dry mix knob. That's like claiming a given automobile is one of the top 5 because it has 4 wheels AND a radio. Ditto for the 2x oversampling feature cited for PSP Mastercomp, which every compressor in the world today has.
I will agree that Melda's MModernCompressor is quite good. But if you're one of those folks who already find Meldaproduction UIs confusing, you're really not gonna like this one - it's idiosyncratic even by Melda norms. Melda's own MDynamics is a much more full-featured compressor.
Hearing that FabFilter was represented, I assumed Pro-C would be on the list. (It has a high-pass sidechain filter too! And a low-pass as well.) But instead they include Pro-MB, which isn't even a compressor in its default mode (it's a dynamic equalizer) and isn't best-in-class in either category.
You have to wonder about the motivations of whoever put that list together.