Have noticed increasingly a problem with my brakes. There is a pulsation when braking at higher speeds, maybe over 40 mph. No noticeable loss of braking power. Am fearful this is rotors, which I know are expensive. Any chance it could be something else and or just pads? This is a city beater car, about 220,000 miles. If rotors slightly bad, is this dangerous? If rotors and pads do need to be replaced, any recommendations for a place that has less expensive parts? I wouldn't be doing this myself, would let my mechanic do it.