I'm gonna be totally honest and admit that I have a bit of a man crush on Ryan Hall. That 50/50 entry I hit at the last tournament was something I started working on after seeing him using it (and then saw Jason Eisner working it on MTS. Thanks Eisner!). I picked up his 50/50 and Triangle DVD set and I think he's a freaking genius and one of the best teachers I've ever heard on the subject of Jiu Jitsu.
As far as him "dissing" the Rubber Guard, I don't know about that. He definitely says you shouldn't just pull your foot up in front of your face all sloppily (and I think we would all agree that this is true) and it's clear that he steers people away from that style of guard, but he doesn't bash Eddie by any means. If someone has personal experiences with him to the negative, I can't speak to that. I've only met him in passing one time so it's not like I know the guy personally, but I know plenty of people that have been to train at his gym and they all speak very highly of him.