One of the downsides of having a system that makes everything sound utterly listenable is that... you tend to listen to everything!
I've just gone through Led Zep I and II over my morning cup of masala chai. I started on III but thought I'd better get down to some work - will get back to III this evening (and probably IV too).
Man, there's so much great music and musicianship in there. Doing a search on this forum, it's clear that many people already know this, but I thought I'd share anyway... just to give LZ a 'bump'.
And the SQ is pretty good too. I have the 1993 boxed set ripped to my NAS. I and II sound really clean and fresh with great dynamics. The bass is every-so-slightly lacking (like all recordings of that era seem to have), but it's certainly there and very tuneful. III seems to be flatter and a little more compressed (the first couple of songs at least). But still better than many of today's offerings.
And if you haven't seen the Kennedy Center Honors to LZ, you need to see this:
https://www.youtube.com/watch?v=pEly-0VLMsA... And make sure you watch right to the very end.
Mani.
Edit: It just occurred to me that my post makes it look as if I've just discovered LZ. I've actually been a fan since I was 15 or so (late 70s).