Scratch X is amazing! One of my friends introduced me to it a couple of years ago when I bought my Rav4 the previous owner had apparently driven under trees a lot, the entire roof and a lot of the hood looked awful! Scratch X made it look new again! It worked awesome on my 4Runner too!!
It has a fine grit to it that breaks down as you rub so if you have been working on an area and move to another one and it seems to not be working as well (even though your towel is still wet) try putting a little more product on the towel.. It may have broken down too much to work.
We have found that using a couple drops at a time works the best so that you're constantly refreshing it without using a ton of it.
Just make sure you wax it after cause the scratch x will take off any type of protective coating you have on it.