My experience is that the one that enjoys doing it the most, gives it the best. I have had both a gay man who knew the territory well, and a woman that just adored doing it, give me the best experiences.
You get someone who thoroughly loves it, wants it, and wants to make the experience the best they can give, will leave you in awe.
Those that don't pale in comparison. When you get a person as above you know immediately.
I voted 'married women' though I hardly qualify to have an opinion as this is the only 'category' I have experienced. But it's the combination of her pleasure doing it, her experience, and her intense adoration of the cock which has taken her so often into bliss, which makes the experience so exceedingly distinctive for a married man whose wife is into this. - IMHO.
That said, my second vote would be 'men', as I imagine myself and other dudes doing this as well as my woman does and then - in terms of lustful, energetic, deepthroat, copious slavering, fuck-my-face - more so. That would be well wild and highly erotic, but lacking the true 'worship' element which makes my number one choice unassailable.