I went through the tour for my sister (who is doing the HSC next year) and I really liked what they had to offer... particularly the fact that they structure it so well. And the fact that they mark your responses for you.
The only catch is that it's still just for one subject. Doesn't help you with the other four or five.
As Sarah168 said, you'd have to be quite dedicated to use it effectively. I think it would be more useful for a parent who wants to help their kid get through English.
Oh... the $375 price seems okay, but it goes up to $575 next year, which might be a bit much.
(This is an honest post... I'm not obliged to say any of it.
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