when ever you get new rotors you need to heat treat them or they can warp easily. i forget the exact procedure but it consists of not letting the car come to a complete stop and not dragging the brakes and doing it repeatedly. then letting the brakes cool for 15+ minutes.
your brakes were probably warping because; A. you were braking and turning hard or often. or B. you didn't break in your brakes when you first got them.
a good set of pads and solid rotors should do you fine.
remember. your brakes are only as good as your tires.
Current:2013 Candy White VW Golf TDI
Sold:2004 Silver Gray M3
Mods: Dice Unit, EAS Angel Eyes, Painted Reflectors, CSL Diffuser, Smoked Corners, PSS10s, 15mm Front and 10mm Rear Spacers.
Gone:1990 Brilliantrot 325is
Mods: Alpine speakers and HU, Euro Projectors, Magnaflow Muffler, Euro Smoked Tails and GC Coilovers.