I have mild-moderate acne and a darker skin tone which means I pigment VERY easily from acne. Ever since getting a Clarisonic Mia in August, all of my PIH has faded significantly within weeks. It depends on the mark since some seem to be darker than others, but for example, a zit I got about 3 weeks ago is already faded completely.

I have no doubt that it's my Clarisonic, since it's the only new thing I've added into my routine. I'd guess the daily exfoliation is what is speeding up the fading. I highly recommend it!