Hi Sparky 25,
My son is in year year 7 at DGS and live in zone A too. His score was pretty much the same as your DS.
He has thoroughly enjoyed his first half term. The first week was "tough love" where the ground rules were laid out to the boys. Now things are more relaxed, as the boys have settled into the DGS way of life.
Homework is regular, but not too much that it takes over family life. We ask DS to do his homework the day it has been set. There is a slightly different approach to the work, implementing the middle years IB programme, this makes it more interesting, not more difficult.
No complaints re not understanding lessons etc.
My DS is very happy and loves every minute of it!
The bottom line is whether you feel it is the right school for your DS.