I have asked around as much as I could, especially from students currently studying CS at IBA. According to them, a lot of the teachers there are also the faculty at KU in its CS program. Which is a positive thing, since KU's CS program is really good. Moreover, IBA has been upgrading their infrastructure for CS (as well as other depts). They recently sponsored some students for an international robotics competition, which is really cool. And for me personally, IBA is just 5 minutes away from my home.
I had originally decided on FAST's test, but then skipped out on it due to a couple reasons. Foremost being: they have made the university in a fucking jungle. It literally takes me 1:10 hours to get there, which is tedious and exhaustive. Other reason, and more important one is their high acceptance rate. If all they care about money and not about the aptitude of the student, then I think you won't much in-class competition. I know two guys -- absolute shits -- managed to get into FAST.