I have rokblokz and I think they saved my vehicle from lots of dirt being flung down the sides. They don't stop it all, but it's a day/night difference. What I don' like about them is the price.
I saw some dude on another forum asking about his "badlands" that he wanted to buy and it had the stock obx wheels and tires on it. He had 0 clues that the badlands has a different size wheel and much different tires.