The US version (yep, I watched it ) is almost scene by scene the same for the first episode and then it gets a little different because they mixed up some of the characters. But, a lot of the story lines and episodes are the exact same, word for word. Don't waste your time unless you are REALLY boredSkins is the only show I really watched one episode after another and just stopped as I couldn't find more of them on YouTube. I just know episode 1, 2 (generation 1) and 3 (half of generation 2). I really don't want to watch that US remake (I HATE US remakes in general) and I'm also not sure about generation 3+.
Generation 3, I also watched, because I am a Skins addict, but was not nearly as good as the first two generations.