Actually I think gun to my head I would take Jack Sock’s volleys. When he plays doubles it’s a legitimately electric experience.
The thing about Rafa’s volleys is that he has the best approach shots and ground game, and you really only see him come to net in advantageous situations. So you can’t separate just the volleys from the overall player.
If he was playing true SnV every point like Goran, Rafter, Henman etc then some of his flaws would be more maginified. For example, I would never say he’s a better volleyer than someone like Sampras.
But all that said, he has great volleys for this day and age and uses his forays to net well. He deserves credit for developing that part of his game, it was definitely lacking in his early years. The truth is he is a smart, complete tennis player in every respect and has almost no weaknesses.