I like scratch-X, especially for noob use.
Why? Because its not really aggressive, and, it's a diminishing compound, meaning the more you rub it in, the smaller and less aggressive the particles get, meaning the more it turns from a mild-rubbing-compound, to an ultra-fine polishing compound. Why is this good? Because it is nearly impossible for someone to rub through clearcoat or paint with this stuff (unless they are repeating the application numerous times with a new blob of Scratch-X every time!).