Apparantly 80% of secondary school teachers thik that SATS are not a valid way of measuring a child's ability. I read that primary schools can/do "teach to the test", so with enough coaching a good SATS score can be achieved but it may not be a true reflection of the child or the school.
I've just taken my DD out of a school that I wasn't happy with. Even though it came in the top 8% of primary schools in the county for SATS it got a terrible OFSTED (notice to improve). After a lot of research I've decided that Ofsted and my own instinct are the better judges. Every teacher I've spoken to agrees. She's moving to a school that seems great, other parents rave about, has a great Ofsted and doesn't publish its SATS scores so I have no idea what they are and don't care.