I'm always faster the more cant I run, fluting or no fluting (not completely sure why, but I believe its because you roll over bad joints as opposed to sliding across them). Its whatever I can squeeze through the wheel bore.
As far as the ndfw, I have not ever canted that. recently, I have stopped raising it as well (and just drill it at the same height as the dfw). if you are running enough dfw cant, it will raise the front of the car enough so the ndfw clears.