I tend to prefer AFC, but then I'm also back button focusing so AFC can behave like a lot of different modes depending on whether I'm pressing the focus button or not.
Back button focus lets you set it to AFC or AFS just by holding the button or releasing it.
Back Button Focus is a great tool for so many photographers and is something I think everyone should try at least once. Below are a few sites that talk about the how and why of Back Button Focus.