I love to walk the aisles around car care while shopping at the big department stores. I often notice the engine additives like Slick50, ZMax and Mystery Oil amongst others with their shiny boxes. I also notice in my car magazines Xado and others in the past claiming to reclaim lost horsepower and more.

Does anyone use these with viable results ?? Anything unique you have found from using these items. I have personally always thought of them as high price snake oil, but always open to change.