Yeah, that "old school" thought of 8x was when they didn't have such cool powerheads. I got my first reef tank almost 20 years ago and I remember the choices. Not so good and really expensive.
In my more recent tanks I have been doing about 4x per hour, but MP10s and Gyres to keep circulation in the tank high for my SPS.
Since this is my first drilled tank with ghost overflow, I am curious what GPH I will NEED in order to keep the flow silent. Now I'm a little worried it will be more flow than I want into my sump. I'll find out this weekend when I get it wet I guess.