I got a 12 string about 6 years ago and loved it for a month or so. I very rarely play it anymore, but it's not because I don't like the sound or anything. It's because it was a gift so I didn't get a chance to try it before I got it and the action is ridiculously high. It's hard to play anything past the 3rd fret.
Just make sure you try as many as you can before you buy it. Though I guess that's something you should do with any guitar, not just a 12 string.