Bit of background, ours have been in private school since nursery apart from 2 years where we tried the local church school.
We moved them not because of the school itself but down to a group if bullies who were awful and when our DD moved they got their teeth into another child who then went on to fail the 11+ as a result of these little witches, seriously this other girl was one you'd have bet your house on passing but she was so unhappy in year 5 and 6 there's no other explaination, she just didn't want to go where these other girls were going, they have all of course passed and are off to the best grammar in the country :-(.