I like it provided it looks like it was done intentionally and not accidentally, if that makes sense. Stackable rings in white gold/silver and yellow gold, several bracelets in different metals or several chains in mixed metals works for me. But wearing a YG necklace with WG earrings, for example, looks random and doesn't work for me. Overall, though, I've decided I am much more of a YG person, so I don't mix much.