As time goes on, you can pull up crap from the bottom of the tank,and screw your injectors, and more. I try and refill our cars when I'm down to 1/3 tank, unless on a trip.
I am still not buying grinding brakes as normal --- sorry this is the first one many cars I have owned and NEVER heard it before. Glad you love your Edge, wish I loved mine. Thanks again for your input ...