The industry recommends swapping to new rotors when switching pad compounds.As Sheepo pointed out, some people don't have long downhill sections. I do, and the thing I will ad is this, I went from 3 sets of metallic, to my first set of organic, and was a little disappointed. Now that the organic pads are 5 rides old and bedded in, they seem fine, until I get back onto other bike with metal pads. The difference is very minor though, but it is there. Both bikes have same brakes, with finned pads. These new brakes with metal pads seem very quiet too. I don't think the metallic are very noisy, and the performance is better. Again, I have some 2000 - 3500 foot descents.