Went through the same thing and I had a solution that worked and was cheaper than all new rotors.  It isn't warped rotors its deposits building up and causing them to have symptoms like they are warped.  I had two sets of rotors.  I would have a set turned at an auto shop, swap them out when they got bad, and have that set turned and ready to go again.  Would end up doing it about twice a year.  Took about 20-25 minutes each time.  I'm positive this will solve your situation and all you're out is a second set of rotors.  Pads seemed to last forever.