We have experience only with FS, it's our second year at Metropole. My daughter loves to go to school and both her teachers from last and this year are great. The only big issue is that the school has doubled since last year and is really crowded now. Grades have 30 kids per class, facilities are not enough for 2000 students, for example classes have to take turns in their swimming, we just had swimming for 2 months this year.
The usual hiccups for any new school but all handled well by very professional teachers. I heard that they have the highest student retention rate of any GEMS start-up school