Top Private Schools in Brisbane?

My understanding of the top tier Brisbane private schools:

Boys:
- Brisbane Grammar School
- Anglican Church Grammar School (Churchie)
- Brisbane Boys College (BBC)

Girls:
- Brisbane Girls Grammar School
- Somerville House
- St Margarets Anglican Girls School

From what I know:
- BGS & BGGS are sibling schools
- BBC & Somerville House are sibling schools
- Churchie & St Margarets are sibling schools

What do you know of these schools?