Now I need to ask my own question!
Having got our son through this 3 years ago we are now in the fortunate position (!) of tearing our hair out about our choice for our DD. I posted previously in the Private Education forum but the forum is less busy than this thread.
She came through the same state primary as our DS (as above, who went to DC), and, to be perfectly honest, did better than we expected and got offers from 2 GDST schools and JAGs (which was the academic stretch goal). One of the 2 GDST offers also came with a dual scholarship (academic + additional). They are all within easy distance of us so there is no obvious bias there. For those who know the area and the school choices it might be obvious which the GDSTs are but I'm hesitant to name them.
Academically JAGs is a step above the two GDSTs and the GDST that has offered the scholarships is possibly seen as the weakest of our 3 choices academically (certainly at GCSE), but is also seen as a kind, small-ish, pastorally focused school.
The normal advice is likely that our DD would do well at any of the 3 schools, but would perhaps be more middle of the pack at JAGs, but surrounded by more academic peers to inspire her (or perhaps destroy her confidence!). So, ultiamtely, would she be served better by being top of the class or by being inspired. Additionally the fact that the GDST that offered the scholarships has moved to a standard of 9 GCSEs rather than 10 (and results have not wildly improved) bothers us, as I have always felt that one of the benefits of private education is the broadness of the offereing.
The choice is complicated further as an aquaintance at her primary is also likely to move on to the same GDST, and that has turned our DDs head a little so she naturally favours the one that comes with the accolades and the chance of not going alone. We both can't however shake the feeling that turning down what JAGs has to offer (which is considerable in comparison especially facilities-wise, irrespective of academic results) would be a big mistake when looked at over the course of 5-7 years!
Anyone out there having to make similar decisions, or perhaps have picked a less academic school for a bright girl and felt it was the best choice?