Yes it is a fantastic school. We didn't take up the place offered as my daughter was offered a closer grammar school.
We loved everything about it, the fact that it was co-ed, the playing fields, the high results and that it was quite liberal and laid back. But for an eleven year old travelling by herself it just wasn't an option.
The main problem with getting in is that you have to live within 1 hour of the school by public transport.
The first exam is in the Autumn half-term (end of October). It is Athey non-verbal reasoning. I think they just do Codes, Analogies, Similarities and Matrices. If they get through that then they are invited back to sit the Verbal Reasoning (Athey). They also sit Maths and English but these are set by the school.
Usually about 1800 apply for 180 places.
At the school's open evening they sell past papers in Maths and English and also the Athey papers. Unlike a lot of schools everything to do with the exams is very transparent.
The school's website is http://www.latymer.co.uk/
All comments from friends who have children there are very positive.