What It all boils down to, is the best setup for your specific application. ( I know that was a little too general)
In addition to all the above mentioned variables, it also depends on what each driver wants.
Even in the pros you can have drivers even on the same team that disagree on specific settings, one wanting the car more "loose" than others.
All I'm saying is that one specific setup recommended by anyone isn't going to be perfect for everyone.
