I think it depends on your scanner, choice of paper, and how flat you can get the prints. I've generally been unhappy with print scans, because of artifacts that can show up from the print surface, but others seem not to have this problem, and I suspect that has to do with choice of paper and the way that it interacts with the glass and the light source on their particular scanner. I find it easier to use a DSLR on a copy stand with lights and standard photographic copy techniques for copying flat artwork.