I think the format of the JMSS test changes each year, so there's not really that much I can tell you (I was really surprised when we weren't tested on literacy). If you're genuinely interested in Science and Maths then you'll easily get in, you might just need to brush up on your skills a bit. Also expect the unexpected when test day comes, so practice your literacy skills or at least work on your essay writing.
Really though, the test isn't too hard and it's nothing to get worked up about
In terms of whether it's a good school, umm...... there's a big workload compared to other schools and a fair bit of pressure, but you'll be part of a very strong cohort which is good I guess
Also we use technology in almost all of our classes (tablets, iPads, etc) so that's something you might want to think about.
John Monash is pretty good from what I've heard (although obviously MHS and Mac.Rob are far more superior )!
You haven't heard of their results because they haven't had a graduating year year They had some results last year, but that may have been for their yr11s (I think).
Yeah no graduating year yet, but our yr 11 results were pretty good and will probably be even better this year
http://bettereducation.com.au/Results/vce.aspx