ken ca
I'v never had one slip, and I didn't bother to sand mine, even tho' it's recommended. Mine don't rust - well, it is CA - and I never get damage on the workpiece because if it's a surface I care about I put a small piece of scrap wood under it. I love them, and for the price they are a bargain. OK, I admit they're a piece of bent steel but who cares?