I'm not a huge fan of Rush, but have known some prog fans who put them at or near the top of the entire genre.
It may sound stupid, but I've always admired Rush's work ethic. In a decades-ago interview, Geddy Lee was asked about their grueling touring at the time, right after they broke big with Moving Pictures. By that time they'd already had a string of successful albums, but MP got much more airplay, everywhere. They were doing over 200 shows a year or something, and GL said, it's the only way to really learn our craft.
Somewhere around here I have a copy of Feedback, their covers of songs from their (and my) youth. I prefer their version of The Who's "Seeker".