powerstop is a pretty decent rotor from what I hear.
I use brembo blanks with porterfield r4s pads on my car at the track. I hear the Axxis Ultimates are better for auto-x though because they have better cold bite. I have no idea how your heating up brakes enough to cause fade at an auto-x
Since your obviously worried about cost.. (totaly understandable)
Buy -
1 qt Ford Heavy Duty brake fluid - ~$6
2 Front Brembo blanks - $60
1 set of front Axxis Ultimate brake pads - $70
total ~$140 that will seriously improve your brakes.
If your think your rotors are getting hot at an auto-x, what your probably experiencing is fade from crappy OEM pads that have glazed.