I get "food poisoning" fairly regularly (maybe once a month?), so I've probably had salmonella before, but (1) I don't know for sure and (2) even if I did, I wouldn't have a clue as to whether it came from the reptiles or from food.

I let my reptiles crawl on my face if they like (I just close my mouth, hee hee). I don't kiss them, either, though I have been known to eat and handle reptiles at the same time. It doesn't happen often, but it does happen sometimes. I know the threat is there, which is why 99% of the time, I take the appropriate precautions. But if I get salmonella from my reptiles, it's my fault, so I'll just deal with it.