I think it's stupid and disgusting. No matter how many diamonds you have in your mouth when I see a mouth full of rocks and metal I'm just going to assume you have f**ked up teeth and have no common sense since you spent God only knows how much to look like a dumb@ss
I don't think they're flattering/attractive or anything remotely close to that.
I do, however, think it's cool for people to express themselves. In whichever way they choose.
i like it I'm attracted to guys with grills. well not all of them just the cute ones! I mean some people gauge their ears, some pierce their body and get tattoos, however you wanna express yourself is fine with me