Buffyverse vampirism is super, super, SUPER lame. They're not even the original person. They're soul is gone, so that means the person is dead and in heaven and hell, right? And there's just a demon there. So you wouldn't get any benefits at all, basically you'd be gone and your corpse would be walking around possessed by a demon. And you'd have a fugly vamp face. So...no.
There are other vampire universes in which vampires are far more appealing.
If I *was* going to choose to be a vampire, I'd want to be one in the Twilight universe. Fiction-wise, they're not that great, but if you had to live as a vampire, that would surely be the way to go. Sunlight doesn't kill you, you're insanely beautiful, and you're basically indestructible and to be really killed for good you'd have to be ripped to pieces and burned.
But no, I don't think I'd ever want to really become a vampire, because I'd like to raise a family, grow old and experience the human life. Living forever on this planet wouldn't be that fun for long.