For perspective, I have owned (and played) over 4k LPs. I have listened to most 2 or 3 times (some many times).
All of the aforementioned LP labels have some imperfect engineering/pressings.
In my experience, Harmonia Mundi and Impex have the best quality control in the business (aside from ERC, which is Very expensive), though I have not hear every label.
The worst has be Columbia.
In between these two:
Cheskey - excellent, with only one or two out of a dozen that was unacceptable (poorly engineered).
AP - very good to outstanding, with many excellent titles, yet too many accentuate the upper-mids and I have had an occasional dog.
MoFi - excellent to outstanding, with many excellent titles, yet variable. I love many, but hated the re-releases in which the original tapes were Dolby-A processed (Bless Their Hearts - what were they thinking?).
Angel 'Sonic-45' -usually outstanding a real sleeper if you have not listened to them.
Mercury original pressings - great at times, but highly, highly variable.
RCA - very good, same as Mercury, but the best Mercury LPs are better than the best RCA.
London/Decca - excellent, Iove the natural sound, but newer releases seem to be below the old standards.
EMI/Angel - Excellent, highly variable.
Back to the OPs question - It is much more valuable to discuss specific releases, of specific titles, by the same performers...
