Amansker, if you have the original transfers from the '80s, then you have Barry Diament's mastering on all but 1 - Joe Sidore mastered LZ IV. Except for the compilation by Dave Collins I mentioned above, these are by far the best digital transfers.
The later remasters by Marino, and the final digital transfers by Jimmy Page, are not as good as the originals.
Now with the Mothership, there has been some very fancy fiddling in the digital domain by John Davis at Alchemy Mastering using Page's digital transfers to produce the sound you are hearing. You might wonder how they managed to get that drum sound.
I'm happy you are enjoying Mothership. I just want to remind readers that no one went back to the original analogue tapes and remastered them. They took Jimmy's digital transfers and worked some magic on them.
Regards,