Are you asking: "What do some of the Muppet performers or Jim's colleagues think of the book?" If so, then I'm pleased to say that I've spoken with many of Jim's co-workers and performers, all of whom have said really nice things about the book.
If you
click here, it'll take you to my website where I've listed pretty much all the reviews, and you'll see comments from Frank Oz, Dave Goelz, and Fran Brill. (There are lots of others who've sent me nice messages in e-mail and so on, but those aren't cleared for public consumption.)
The book as published even used Oz's "blurb" on the inside cover jacket. That was a really big one for me, as I'm delighted that Oz -- who knew Jim probably better than anyone -- thought I'd "gotten" Jim.