I selected the triple skid plate deal from Primitive Racing for my first SK Forester. This included the engine skid, transmission skid, and the rear differential skid. I have been using them for 5 years and they have held up very well. They are 3/16" thick aluminum, but I would prefer 1/4". My only other complaint is the vents that are pressed into the aluminum. They look cool, but they don't offer real ventilation, only a rough surface that prevents sliding, holds dirt and mud, and weakens the structure. After a while, I removed mine and used a 4 pound engineering hammer and some pavement to close the vents.