Cherwell is an excellent school. It is in North Oxford. They send as many YP to The bridges as most of the independent sector you do need to live quite close to the school to get a place. Often even children in catchment don't get places.
I have two friends whose children go there and they are very happy with it. The brighter ones get a lot of additional support so the emphasis is not just on bringing up the strugglers.
I would not rely on OFSTED reports. They are often done 4 or 5 years ago and schools can change a lot one that time. I would go and look at a school and talk to YP and their parents. It can be hard to unravel GCSE and A level statistics at comprehensives. If I had a brighter child I would want to know that the school streams at least from year 8 in some subjects and beware also of schools that only offer double science and not triple and that have an over emphasis on tech subjects, that is unless your DD is that way inclined of course.