Always use Super (premium) in my 350
No break in
I had them put all season tires on mine ( I am in Nj) they were hard to find because of the size of the wheels (16") - but they did find them - no they are not snow tires, but they are mnot summer tires either..they are a bit better, and I turn the "snow" traction button on and it's pretty good in the snow,