I have the factory Ford that are available at the dealership. They seem to look ok but they don't really come out very clean at the automatic car wash. You almost have to detail them a little yourself if you want them to look great. Armor- all or a similar product works good to keep them looking good.
I have those on my Tacoma.
They're shorter than the OEM mud flaps which tended to rub the ground on occasion. They're also wider, though, so the crud doesn't fling up onto the body as much.
But they're SUPER rigid and if they made contact with the ground, you could end up ripping some bolts out of the fender area.