For me, it differs depending on how you interpret "intimidating".
I have a deep respect and appreciation for GSDs, Rotties, and Dobes. I think they're gorgeous and one day, I might have one of any of those breeds. But man, they do intimidate me in a "I'm not worthy" and "you're a little scary" kind of way. Maybe it's the coloration? LOL
Chows intimidate me in that I don't trust them. They make me very nervous.