I don't mean to hijack Sharkey's thread, but I'd like to post an update on my situation. My original boots are Raichle/Deeluxe SB 423 size 28. I just replaced them with UPZ RSV (predecessor to RC10?) size 27. I am using the black thermo liner size 28 from my old boots and they seem to fit well. The size, shape, and stiffness of the UPZ works much better for me. They're smaller overall, since they're a smaller size, but still have plenty of width in the forefoot, and a much narrower heel. I'm getting very little heel lift now. I've only had them on snow for a couple of hours, but I'm sold. I can't wait to try them again.