I didn't go to HS in the US. It was a very selective HS with an admission process similar to when you apply to UNI - qualifying exams and the whole shebang. Admission ratio was 1 in 75/80 (being serious here). Many of the things you would study in 1st and even 2nd year courses at US uni I had already covered in HS.
And yet, my undergrad life was hell, at least what most students would call it, by my own design.
The thing about US education that I like the most is that it gives you flexibility/choices, which is why I said what I said earlier.
In HS I had a set curriculum, no options or choices, just a 24/7 grind, which is the exact opposite of most HS in the US, from what I gather. The negative is that it could be a burn-out factory, if you can't keep up.