Just remember, if it's the hygiene factor that puts you off, that the mouth has more germs than pretty well anywhere else in the body.
I"m totally in accord with the feeling you might get if your man goes 'all porno' on you and tries to force you to do it when you're not ready, but I also have to say that biologically it's hardly any different from kissing him.
As long as you are doing it when you choose to, if you enjoy him going down on you than you owe it to him to return the favour, even if your verson of it only involves licking it a bit. Deep throating is essentially a party trick and unless you're eager to do that, I'd recommend avoiding it, but if it's reasonably clean I can't see how you wouldn't want to give it some attention now and again.
50 years ago it was probably different as men's personal cleanliness wasn't generally so good. Women, though, are quite literally thousands of times more likely to get infections down there than men, so what's to stop you?
By the way, what men eat will alter the taste of their semen so you might be able to improve your chap's diet and make him taste better ...