I live in West Michigan and have a SAS package on my OBX and haven't had a problem the flares are larger on the SAS and running boards on the rockers keeps most everything off the fenders.
My skid plates came plastic I ordered a MOD bumper took it back to the dealership and they did a little mis-build form and now they are ordering a new set this time steel. Make sure to check the bash plates this happened on several models with the MOD bumper.
Don't read to much into what other people are complaining about their Bronco. I love mine can't believe it's sitting in my garage after a 2 year wait. I love the ride I love the look and best of all it's all MINE. So let others complain about the small stuff, enjoy your new Bronco!