Here's what I've heard and confirmed for myself:
Essentials: Clear and concise points, brilliant questions, sometimes going beyond the scope of the course to train you to think laterally. Some of my friends credited Essentials practice with getting them through this year's exam because of the problem-solving style it perpetrated. I find the examples a bit vague sometimes, however.
Heinemann: I found the colourful chapter introductions helpful (yes, childish I know >.<), and as for
reading to understand Maths, I thought this was the best. The rest use slightly more awkward language, and 'speak' more directly to a student with all the assumed knowledge down pat. Questions are not challenging enough for the astute VCE student however, imo.
Mathsquest (Jacaranda): Good calculator examples. Better questions than Heinemann, not as good as Essentials. Layout sometimes confusing.
MathsWorld: Good examples when given; usually leaves out examples for questions they subsequently ask you to do though, which can sometimes get a bit frustrating. Questions on par with Mathsquest, perhaps slightly easier.
Hope that helped somewhat
