Read a few articles where an SHM CD was compared to unknown mastering on a regular CD an they said the SHM had more _insert-positive-audiophile-terms_. However, unless those two discs were digital clones and all other things controlled, it's a no brainer to call BS on those kinds of tests.
There are those who claim to be able to hear a difference between CDs pressed at different plants or one CD-R over another. These aren't just Joe-nobody on the internet but respected music engineers. I have personally never heard the difference and am happy not to. Engineers have stated it's simply not possible for there to be a difference - the error correction built into all CD players handles those problems. No one, to my knowledge, has taken two or more digital clones and thoroughly tested for any differences coming out of the analogue connections on a CD player playing these discs, and then published the results. I guess those technically minded enough to test, in their mind see no need to, and those that hear a difference don't want to have a potential sanity check, dismiss it and then defend themselves. Theoretically, unless the CD is severely damaged and the data is irretrievable, anything else is snake oil and belongs with the green felt pen around the outside edge of the disc nonsense.
In truth, if one looks at the community preferred digital mastering of a particular album, a lot of the time the 0s and 1s that were put on the SHM disc weren't worth the bother of burning a CD-R, let alone pressing a so called premium disc.
At the end of the day, collect a special one for the sake of completeness if you like, but for me the important thing is the data on there.
Sometimes my vanity is rewarded and other times not so much.
