the hydraulics and sensors are the same on all cars. however:
americans tend to complain more about brake dust and noise. therefore, the rotors are cast from a different iron alloy, softer for the us, harder for europe. this results in american rotors warping more often, and quicker rotor wear. it is then not surprising that your e30 rotors lasted lifetime.....
i suspect pad compounds are different as well, this is true for most german brands (volkswagen and benz), and used to be on e36.
it is easy to verify stealership pad story. take of the wheel, and look at the pad sitting in the caliper. if there is about 2mm of the center groove left, it is ready to be replaced.
rotors unless very thin and scored can tolerate a lot, like pmb said. even a significantly grooved rotor will be ok, if you burn in the pads correctly. that is: 10 stops, moderate brake force, from about 40mph, NEVER to a complete stop. then 10 more agggressive stops, and let cool. do the sequence once more, and you are done. also, important to brake in a straight line, not to put side loads on the rotor.