I'll have to say Rebel Yell because that's what I have, but from what I've read the Crawlers might be better for "classic" rock if you mean 70s-type stuff.
As I understand it, they're similar output but the RY is a bit brighter and punchier, more in-your-face. More 80s than 70s, perhaps.
I don't think you'll go far wrong with either. I definitely plan on putting a set of Crawlers in one of my guitars eventually.