I don't call it begging unless they are too desperate to care whether I've already said No. And yes, I love it, to me it's the pure sound of submission.
I once played with a femsub at a time when my primary relationship was still under construction, so I made it clear in advance that sex wasn't on the program. She agreed, but after an hour or two in the dungeon she was hot enough not to care.
And I thought that only a Dom could get as much pleasure out of having a woman grovelling at my feet pleading desperately "Please fuck your slave, Master, a girl begs!" as I would have got out of doing it.