Like said before, it is just a random occurrence and probably has nothing to do with your driving style. It just happens. The price and build quality of the rotors doesn't have as much to do with warping as we would like to think. Heat up a nice high-performance cross-drilled rotor, run it through a puddle, and it's going to warp just as easily as the $30 KIA rotor.

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08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280