Grottyash:
If you're talking about vinyl, this isn't easy to answer since most of their stuff was recorded in mono and only the last couple of albums are stereo. Where stereo and mono was available, the sound quality was different.
The problem also is that their albums sold many millions of copies, which mean several masters had to be used, they were often played on rubbish gear where tracking weight was often achieved by putting coins on top of head of the arm. The odds of finding a pristine original pressing from early in the first run is remote, as prices for these gems attest.
As to the remastering, they are a modern-day interpretation of how people to-day thought the music should have sounded back then, so if best-sounding means closest to what happened in the recording studio, then they probably aren't so good. The original CDs came up to twenty years after the original records, and used stereo mixes, some of indifferent quality.
None of which matters, because as David of FHHF says, the music is more important than the sound quality.
I have the Mono box set, and I really enjoy listening to it. There's also the "authenticity" factor of these contemporaneously being the versions most people would hear, at least until stereo took hold.
Yes, of course, it's all about the music first and foremost, but I was just intrigued to know what other people thought of the relative merits of the numerous editions of The Beatles canon.
I should add that I've got most of the 1987 CDs, the 1978(?) " Blue Box" set of vinyl, several digitally remastered vinyl cuts, the Mono Box and most of the stereo remasters from 2009, and a couple of 1960's pressings too. I have yet to hear any of the MSFL or is it Sound Lab pressings, but I'm nerdishly anticipating any future Blu-ray or new vinyl editions. So it is in this context that I'm interested in how they compare sonically.