Both my primary and secondary schools were pants! My parent's weren't to know though, we didn't have as much of a wealth of information or access to such back then!
Totally agree with SATS only giving a somewhat blinkered view though. I really liked my son's first school and I thought his teacher was fab and the children were really friendly, it was just way too far away to travel to in the morning.
However, it is 60% Muslim (has just been featured in the local rag as being first in the area to offer halal meat at school lunches!) and, of the other 40%, a great deal is made up from other ethnic minorities.
A lot of the kids there were pretty fluent in English by the time they were set to leave for secondary but, at my son's age at the time, there were a huge amount who couldn't speak English at all and, as well as being probably quite difficult for the teachers, probably reflected badly on their SATS report, not because they weren't bright, just because they didn't understand what was being put in front of them?