They'll etch, they'll do all sorts of not-good things. Don't run good stuff in there if it is antique, etc. Or at least don't use the caustic commerical soap.

You'd be surprised how many places want the old incomplete sets to turn around and sell to those who are trying to complete their own sets. If you're not using all of these things don't just chuck them in a garage sale, surf the web and find some of the services that match up china (many of them also do silver and flatware).

SRS