what type of track work are you referring to? just random track days or like competition with rules, even saying that i dont think 5stud is a must on any track rule..
What type of engine and power are you hoping to have or already have on the car?
If your dead set on a 5stud Nissan brake setup, get R32 GTR brakes setup, lighter, stronger, and i think there is a setup selling for dirt cheap on nissansilvia right now, cheaper then 4pot s15 setup
but like i said, how much Hp are you expecting to run on the car..