For me its like anal sex... the fantasy is great, really hot, but the reality is not as good as the fantasy would suggest.
Like many guys, I used to get the urge to taste my own cum, but like everyone else, as soon as I orgasmed, the urge would be gone.
I have tried it of course, but the taste just isn't very good.
I'm sure you can grow to like it, just like anal sex, but it seems more natural to swallow someone elses cum before you yourself orgasm. That way the desire is still there. I have swapped cum after hot oral sex with my girlfriend, or licked some up off her nipples and belly,and that we both liked!
Personally, I think pre-cum tastes great, very buttery and seems to act as an aphrodisiac of sorts (at least to me). I wish cum tasted like that, I'd greedily slurp it down like crazy!