I would wear one, as any sort of choker tends to look pretty flattering on me, but I've come to permanently associate collars with the obnoxious 'I'm really deep because I like BDSM. Stupid vanillas would never understand!' folks from my hometown.
Actually, I've always been a fan of guy-style necklaces (wooden beads, bone, my actual dog-tags, etc.) and like to wear them because I think they just add to an outfit. As far as collars go, I've worn chokers before (went through a punk phase) and wide band collars, and it felt fine. But then again, I don't act obnoxious with em on, so most people barely notice or say "nice choker, dude".
I have 1 collar that I wear, and thats only because it lights up. And I can attach random metal things to it. People are allways asking if its a shock collar because of the battery pack/solar pannel on it. I love the thing, but im nones property, so hell if you can get a leash on it. >:3
Geez, I don't get the "I'm not subservient or an animal/pet or into BDSM." responses. Since when did a collar HAVE to mean those things? I consider it just an accessory like any other necklace or choker. Spiked ones do make some assume you're into goth/punk or something. And yeah, people can assume a regular collar means something about you, but you can simply tell them it doesn't, and if you mean what you say then what's the big deal? It all goes with what you think you'll look good wearing.
So yeah, I don't wear collars or chokers myself. But I might somewhere down the line, or I might not. It really doesn't matter that much.
I do wear a silver necklace with a ring on it. Almost rocked the turtleneck and chain look by accident because I'm just that white-bread, but I don't like beer of any kind.
I don't wear collars for the same reason I don't wear ties, it feels like a noose. That, and my fursuit (squirrel) would look weird with a collar. And yes, my avatar is actually what my fursuit looks like.