I've never heard the Mosaic but those other ones (Free Fall and the 1961 set) are the only discs by him I have heard, and I enjoy all of them. I was lucky enough to find those at the local library back before I moved.
Get the recent The Easy Way Verve reissue. It's from pre-Free Fall era (in a trio with Jim Hall and Ray Brown), so it is quite different, but very charming, clever and quetely experimental (but much less so than the Free Fall trio, of course). It should be available cheap everywhere.
Thanks, it's on "the list"... (as are many of those Verve LPRs, too many)
Sounds like the Atlantic trios - though the later Atlantics, with Giuffre/Brookmeyer/Hall are something else again, replacing bass with a second horn was quite an idea! Quietly innovative, that's what Giuffre was, yes.
Also his playing and that folksy vibe he had was sort of like a "poor man's" Horace Silver, or rather: a countryside version of the "folksy" (or rather "bluesy" and "urban") hard bop music happening at the same time.
I don't know the Sanders ESP, by the way. Have some Impulses, but don't really know them too well, would have to listen to them all to post any impressions.
ubu