I have close friends with children at the school, and all are very pleased with it.
One has an extremely high achieving child - he's doing well - and all comment on the quality of the pastoral care.
I went to the open Days two years running and was impressed. I love the vertical tutor groups. I think the setting rather than streaming will suit some kids better than Dunraven for example, which streams, so less good for students who excel in some subjects and struggle in others.
Elmgreen seems slightly more individual and perhaps more touchy feely than other local comps.
The school had some difficulties with it's first couple of years intake and the first GCSE students to be coming through ElmGreen represent those years. Now the catchment has become smaller each year as it has proved popular and attracted families who have chosen it rather than taken children who had no other offer - this is a reasonably normal process, I think, with new schools.
I see the pupils in the streets and they are well behaved.
Having scanned thru the ofsted report, though not knowing children there* - it's certainly not a terrible report. It scores well for leadership / management which is a good indication there's capacity for improvement.
You could try comparing the report with other schools that have moved satisfactory to good / outstanding, to be a pupil at a school which is focusing it's attention on improving is not necc a bad thing at all.
(My DD does have one or two friends who go there, but not ones I know well - I've certainly never heard anything negative about the school from them).