I thought Moving Pictures from "The Rush Remasters" series sounded pretty damned good, but I didn't have an older CD to compare it to. I only had my vinyl. So I'm thinking that it would only really make a difference if you're serious audiophile or Rushophile and have a system which can do it justice. But if that were the case, then you'd either have Blu-ray or DVD-A capability.
So the answer is to pick it up on Blu-ray now anyway, because someday you'll have an HD setup, but the price will never be this low again.