We have sent dd1 to local state primary, not the most popular one either, though we looked at two private schools and could afford them.
Reasons being several: prefer state for dd, so she gets to meet people from varying backgrounds/cultures, but would have sent her to private if we'd thought she'd be happier there - having visited four schools, two of each sort, we knew this was the one for her. Head was lovely, school is small, kids are enthusiastic about their school, learning, and keen to tell visitors what they're doing.
One of the private schools we saw (which we thought would be our favourite) was unbelievable in its attitudes to special needs - we wouldn't touch it with a barge pole (though dd isn't SN, as far as we know). The other was nice, but a bit weird and stuffy. The other state primary was bigger, and the head is very ambitious/competitive....we didn't like the feel of the place in comparison to dd's, though they have much better/newer resources.
So far, we couldn't be happier with the choice we made - mostly on gut feelings, and talking to parents who have kids there already. We chose with the idea that primary is for helping kids learn to enjoy learning, to socialize well, and to form a good foundation for future education.