Love them. As a chemist (and as a fly rod builder who routinely anodizes titanium) I'm enchanted by oxidation of metals and heavy metals. And hey, it's my hobby, so if someone else doesn't like em, that's just fine too.
I have a LWC that has some of the coolest toning I ever saw, have no idea how it happened, but its super cool so I like it. I have the 2009 Lincoln 4 cent series that are in Proof and have a weird toning and I'm on the fence on that one. So it can be either.