The expression is one I recognize when I hear it and since it's uncommon here in New England it has the effect of being streets ahead of any other kudo.
Par example : "She is streets ahead of the other students" seems a higher compliment than "She is 'way ahead of the other students" ..... perhaps because of its very oddity here.
It may be familiar to me because I watch a lot of BBC-America stuff on PBS and I've visited GB.
I wonder why it is "streets" and not avenues or lanes or roads ahead?

wow