DINOSGR

Since 1954 all vinyl were to be mastered via RIAA EQ. Unfortunately this was not and is not the case. Even today mastering engineers use different EQ's than RIAA to cut the lacquers. The result is a lot of mediocre sounding vinyl. To me (an only vinyl listener) is frustrating.
One step in changing this situation (I'm taking other steps also, hopefully more effective ones) is rating the vinyl according to this (RIAA vs non-RIAA). So I'm using the following pattern: Hope it will be useful.

Other than RIAA mastering (all ratings after using the correct EQ on each one of them)
1 star = Very poor sound quality or two or more EQ's were used (non of them RIAA - very rare)
2 stars = Good sound quality
3 stars = Exceptional sound quality or 2 different EQ's used (one of them is RIAA - very rare)

RIAA mastering
4 stars
5 stars = Exceptional sound quality

Evaluation phono EQ's via the Clearaudio Phono Statement.

Where we could possibly find 2 or more EQ's:
1. Box set, if they contain various albums
2. Compilations (most probably when the tracks were taken from vinyl and not from master tapes)
3. Reissues of the pre-RIAA era (they didn't bother to find the correct EQ)
4. Different person cut the lacquer on different sides
5. I don't want to comment on that because I'll be very rude