LINE-X is the best hands down.

Rhino fades and you can scrape it off

Line-x never fades, they color match your truck, you cant scratch it, it is really rough so things dont slide around and is warrented for life. I think it costs about $400 I cant vouch for gator gaurd because Ive never heard of it... and I think line-x is the only company that does this but they stick your truck in an oven to bake it in so its completley cured when you pick it up the next day