Your Top Five Blues LPs, SQ-wise...

Only one mentioned Buddy Guy/ Jr Wells, and for a different album:  My all time favorite -  Drinkin' TNT, Smokin' Dynamite
Koko Taylor - I Got What It Takes, or From the Heart of a Woman
Sonny Terry and Brownie McGhee - Sing if you can find it) or Midnight Special (I have the compilation)
James Cotton, Cotton Mouth Man (With Joe Bonamassa and Greg Allman)
Albert Collins - "Master of the Telecaster"; "The Iceman":   Ice Pickin' or Cold Snap

Buddy Guy, Bring Em In and Blues Singer ( both on cd ). Smokin Joe Kubek Show ME the Money on CD.

Joe Bonamassa Blues Deluxe and Bloodline with Joe Bonamassa.

Junior Wells’ “Hoodoo Man Blues”is one of the first real Blues albums and has very good if not reference SQ, but absolutely triumphs on music, which to me is important. 
I also agree with the votes for “Chicago/ The Blues Today” set. Very natural ambiance live sound. Especially the volume with James Cotton and Otis Rush. 
The studio tracks on Muddy Waters’ “Fathers And Sons” are fantastic musically and have crisp dynamic recorded sound. Check out “Can’t Lose What You Never Had”. 
A more recent disc I love is Branford Marsalis’ 1992 set featuring B. B. King on a track called “B. B.’s Blues”. Unbelievable guitar and vocal by the master, beautifully recorded in modern fidelity with a stellar jazz combo. B. B. definitely upped his game that day. 
Love the Blues!

I was gifted an OP(stereo/pink cover/1A pressing) of Fleetwood Mac "S/T" a while back in very well used shape. I’ve spent a lot of time trying to whip it back into shape. I own the MOV version as well. My conclusion is if you love this lp enough, try to find a great OP copy. Check out "Long Grey Mare" perfection!