I have used two of the DesmoParts kits on my bikes. Good results.
I have also bought stainless hardware in bulk on eBay. Good results there too.
My only complaint with the Desmoparts kits is the organization of the parts and the instructions. It would be nice if they packed all of the hardware for a particular area of the bike in a single bag. I swear I spent 2/3 of the time installing the kit looking through the pile of bags for the one with the washer or nut I needed.