Jacaranda Key Concepts all the way, it was the one we used and my teacher said it's the best by far 
I personally wouldn't buy 2, you'd probably never get around to reading both and eventually you'll just rely heavily on one, which I think will be Key Concepts, so better to just get that.
That said, doesn't your school have a booklist that pretty much says you have to get one of them?
That's what i was thinking! With my experiences of purchasing two maths textbooks and ending up only using one, i have a feeling that will happen again next year with health. Well long story short; i vaguely remember my teachers say during Year 12 Orientation that it is best to buy an extra resource (and she showed the Key Concepts book to the class). The 2014 Cambridge textbook hadn't arrived yet so none of the girls in my class had the textbook. And so, my teacher photocopied the 1st Chapter of it (Cambridge) for us to use on the holidays (implying that it was going to be our textbook). She also photocopied the summary section of the Key Concepts book because she said that it was a good extra resource. My health teacher in 2013 also had the Cambridge textbook with her when she took us for parts of orientation. And, the Health/PE coordinator who also took us for orientation when my teacher was absent also showed the class the Key Concepts book and said "I also recommend buying this book for an added resource", again, implying that Cambridge is the one we're supposed to have.
However the thing is, when i went the other week to purchase my books for next year i didn't really pay attention to what it said on the booklist. I just gave it to the bookshop guy and he went and got my books for me. When i came home, i took all my books out and was quite shocked when i saw the Key Concepts textbook instead of the Cambridge one. I then checked my booklist properly and it clearly stated "Key Concepts in VCE Health & HD 3 & 4 Value Pack".
So at that point, i was just confused because all throughout orientation the 3 Health related teachers said we had to purchase the Cambridge textbook whilst also recommending the Key Concepts… So i thought hmm… it shouldn't be too bad considering Key Concepts was recommended and it wouldn't hurt to use it. But i still had to make 100% sure and emailed my teacher but she hasn't replied for like 2 weeks so i ended up opening the packaging of the Key Concepts book. So now i can't return it.
So in the end i'll definitely end up with the Key Concepts book and hopefully i won't need to purchase the Cambridge. However, if the Cambridge does end up being the textbook we need to use for class (even though the booklist says otherwise), i would have wasted $100 on Key Concepts.
Wow, that really wasn't short! Sorry to bore you haha
