Of these 35% specialist places, 60% are allocated to the inner area of Watford postcodes.
The remaining 40% (of the 35%!) are for the outer Watford postcodes.
I believe the split will be 65% inner and 35% outer for 2013 entry.
The VR test was 100 questions in 45 mins last year with a 30 min "familiarity" test before where they ensure all students are familiar with the VR type of questions. The VR required a good vocabulary so lots of reading of fiction, fact, magazines and newspapers if possible. I used to test DS on words in books he read to make sure he understood them to try and encourage him to look up the meanings when he didn't.
As has been stated, lots of practise, 100 questions in 45 mins is a really tough test, it is also about recognising some questions that may only have one mark but are complex and can soak up time.
For maths the biggest advice I can give is ensure maths std is secure KS2 level. Our experience is that it is not particularly difficult, but many questions are phrased to "trick" the students into silly mistakes. This is where the majority of marks are lost in the test papers we did.
Look to do 2 papers of each type each week and a tutor can help as they have lots of materials. However if you can dedicate the time to teach and mark the work, no reason you cannot do it yourself.