I have tried foreskin restoration, using the non-surgical stretching method. I got some results, and I now have a slight "cuff" around the corona that wasn't there before. But I've never been able to stick with this very lengthy process, which typically takes at least a full year.
Also, with stretching you might need to follow it up with surgery anyway, in order to create the tapered tip which most natural foreskins have. Otherwise you get an open, loose sleeve look that many would find unattractive, and certainly not normal in appearance.