I've listened to it all now except the B-sides.
The pressing quality seems fine, I've had better but it's OK.
The actual sound quality seems to get better as the set goes on - maybe GH and STP were never recorded with vinyl in mind so that's why it doesn't sound quite right.
It's made me re-evaluate Kill to Get Crimson, it's better than I previously judged. And I think it works as a "whole album" more than any of the others. It has it's own sound.
BTW, it comes with a code to download it all in WAV.