How to find the good CD recordings?

CD recordings matured like any medium. Take records recorded in the 30's and compare them to recordings in the late 40's and then the 50's. CD technology improved as did analog recordings. This CD bashing is way off and done for marketing to boomers on a dying hobby and a hobby which is driven by boomers. Young folks have their own way of enjoying music and that is free streaming from many sources where there is no need to buy a whole recording but a song of 2 they like. The only thing you have to stay away from is the current trend of highly compression both in Vinyl or CD or Streaming the format does not matter. Look for good mastering labels and if you like current produced music then expect not stellar sound. My experience anything from the late 90's through today sounds good as long as the mastering was done correctly. It gets down to the artist you buy and the recording was produced more than the format. I've collected music for 45 years so I have the experience in both formats and believe I sold many LP's at recorded collector shows that sounded god awful so the myth about vinyl being superior is a myth, it all gets back to the production of the recording, garbage in equals garage out.   

Regarding the LZ CDs in all their incarnations I don’t think there is a unanimous approval for any of them.

Reading all the threads on various forums you get recommendations for all of them.

The key is to find posters with preferences and systems like your own - kinda like food or movie critics.

For me, the Diament CDs are my go to; I’ve tried the 2014 remasters, didn’t care for them. Much louder, brighter/brittle; great for low level listening when the baby is asleep and you want to hear detail. For cranking? Nope - like evil gnomes with ice picks attacking my eardrums.

The Diaments are for cranking loud - for me, for my system, for my preferences.

By coincidence I found the first Led Zeppelin II LP in some thrift in MD. It’s the one with STA etched in the trailing vinyl. Anyone heard it? It’s the one they say had to be remastered due to some cartridges flying out of the groove. But it’s not the SS RL issue.

compression, EQ and bad mastering killed many CD issues of LPs.When CDs 1st arrived, most labels used EQ'd masters to make CDs from, as compared to a 1st gen master mix flat 2 track, or even a 2nd generation flat.
An EQ'd master was made in the days of vinyl to compensate for the physical limitations of vinyl.  Vinyl is really only good for 18 mins per side with decent dynamics.  When LPs became 25 mins per side and the last song was most dynamic, the mastering engineer really had to compensate.  Great ones could make compensation during songs if need be, but most stuck to changes in between songs, so as not to shock the ear.
But even then, when a US label shipped a master to the UK for local LP or CD production, it was still 2nd gen.
I was recently looking for a cut that I knew I had on at least 3 CDs.  They sounded completely different from each other.  One was a US issue and the others on later Brit collections.
A lot rests in the recording engineers hands.  Glyn Johns, Tom Dowd, the Beatles guys - Emerick, Scott, MacDonald, Smith, and others. Brilliant sound with minimal mics.
Check out Buena Vista Social Club for a truly fine recording with space and limited augmentation of sound.  Jerry Boys, old school Brit.

Original CD pressings from the 1980's are a real sonic joy and Remasters, unfortunately or at least 9 times out of 10 sound like absolute rubbish. In the event of remastering, the recordings themselves are just made 'louder' which follows suit to the so called 'loudness Wars'. The decimation of the cd's warm character was destroyed around 1997 when music mastering for the cd in general took on a whole new persona. Above all, It is really quite sad really. 
Long story short. Stick with original cd pressings. Most of the comments are on here that I've read are absolutely right on the money. 
My advice. If you plan to buy a cd that was recorded after 1997 go to drloundnesswarinfo.com
it is a pretty good database of info that tells you the DR value of the piece of music you are interested in. 
Lastly. I must share one remaster that is actually far superior than that of the original and that is Metallica's 2017 remaster of Master of puppets. It wasn't made 'louder' it is an actual proper remaster. Fixed the bloated low end of the guitars that really took over. The sharp treble from the cymbal crashes lost its heavy bite and the vocals were smoothed out slightly. Everything a great mastering job should do! Check it out and happy cd hunting! 

If there is one thing I know. It is great recordings so if you wish for me to give some suggestions to you, especially in Prog rock I'm so happy to help. 

-nicholas