Recent experience of Seaford. DS was there Y9 -13 in the senior school. Suited him really well and he was very happy there. Had good friends and good relationships with the teachers.
They really try to work with the individual young person. DS at different times used learning support as well as using the additional pastoral support through their pink house. We felt that they fully appreciated that DS was not the finished article and there was room and for him to develop emotionally and academically.
They don't select purely academically so there is a range of academic results. (Head says they are selective just not solely academically). Among DS cohort - some off to Russell group for competitive course, lots of other unis too, some to apprenticeships , a fair few gap years to explore interests, a few professional sports folks. Good range of choices at GCSE and A levels with some BTECs also offered. DS probably exceeded our expectations on results as a result of the support given. He is proud of the school and really knows and loves certain teachers who he can personally point to and say they helped him and made a difference.
The school really try to help students find the things they love. Huge choice for sports - and after certain point of rugby, hockey, netball etc not their thing they can play golf, sail, climb etc. DS enjoyed the winter sports but less so summer sports so played golf as a beginner and really enjoyed that. Possibly that's only downside - DS was quite good at cricket at prep school but went off it and was able to opt out. Other schools would perhaps have required him to play. They gave more choice. As a result he gave up as his friends weren't playing. I have no idea if that's good or bad. DS hasn't ever regretted it.
Y9 only a handful weekly boarded by Y13 seemed like half the year (or more?) did. They like being on site socially but also get into the groove for studying.
Down to earth cohort of students and parents.
You don't say what you are looking for but happy to give other input if useful.