CSCST (Main) is a great school. It's campus is humble, even deprived of the facilities that the usual private schools have. BUT, it's teachers are dedicated, it's students are serious in studying, and the atmosphere is conducive to study and recreation.
I have studied in 4 different universities, 2 of them are considered as top schools in Manila, but I can honestly say that CSCST Main campus is where I would advice friends and family to study.