I completely forgot about Grape Jam because I never listen to it. Yes, I don't remember the jams being anything to write home about.
Quicksilver has a ton of official live albums and compilations. Some of them are absolutely inessential to even the most hardcore QMS fans, I imagine I one gave a listen to a live album from 1977 (I think) and it sounded like shit, they played terrible songs, had no chops at hand to carry them through musically, really struggled to kept a steady tempo most of the time, and Dino obviously did so much cocaine before the gig that his voice sounded comically nasal, like a parody. I don't know who buys that stuff. I think there's a small cult of John Cipollina fanatics who would get anything that has to deal with him, so maybe there you go. He's an especially popular musician in some circles of Japanese rock fans, at least Japanese psych musicians I've met/interviewed care about him so much more than about Garcia, Jorma, whomever.