Moonbear: The UK system focuses you very early on what you want to do. Perhaps too early, but it is not disadvantageous compared to the US system where you don't focus as early but correspondingly don't do work that is at such a high level. They are perhaps equivalent, certainly many of the things I saw taught at *one* US university were high school standard in the UK. Europe and Japan are further ahead again.
STEP: for whomever said it was far in advance of the US syllabus, it is also in advance of the UK system. That is its point, to distinguish between able students who find the UK exam system inadequate.
There was famously a girl called Laura Spence who failed to ge into Oxford to read Medicine despite being predicated straight A's at A-level (4.0 GPA) and having obtained several A* and A grades at GCSE. There was huge outcry, Gordon Brown weighed in at the unfairness of it all, she went to Harvard. What was lost in the brouhaha was that she was one of 16 people applying for 7 places and there were 9 or so people who had better grades than her. Plus she ignored offers from other medicine schools in the UK and went to a country where she couldn't study medicine at undergraduate level. They also made a fuss over her grant from Harvard which was only their standard means tested bursary and a similar award might have been given to her at Oxford.
What was the point of that? Oh, that A-levels aren't very good at predicting aptitude amongst the good students, hence the STEP.