It seems like a lot of it depends on where you live. It's great that there are some fab public schools around, although I do think that happens more in primary than secondary. There are certainly no decent public schools in my town generally it is the exception if people do well in our public schools, not the rule. In my town that is.
I seem to hear lots of people saying that they are all for public schools (irl), but they re the ones that couldn't afford private anyway. And by private I don't mean catholic, as they are very cheap here anyway. I know I am the same. If we end up at public for secondary it will be down to money only, and I will probably defend my choice as being the best for my child. But of course I will, as we need to feel like we have done the best thing, even if it means lying to ourselves well thAts how I feel anyway. And I think lots of people are the same, they just don't admit it.