"Quicksilver Messenger Service":   near great

"Happy Trails" (a live record that shows them as a "jam band"):   truly great

"Shady Grove": OK, but decline has started with overtly political and druggy material found in later records (see Michaer's example, above)

the rest of their records: so-what stuff, Valente could say about the advancing art of Rock Music is the early 70s "I got stoned and I missed it"