I had a series of 5 Fraxel Re:store treatments for acne scarring over about 6 months. I has softened the scars and improved my complexion which is definitely noticeable however I still have some deep acne scarring.
I think for acne scarring something like Fractional CO2 is a better choice or CO2/Erbium laser if you have light skin and aren't prone to pigmentation.
I have experienced some hyperpigmentation after the Fraxel however it isn't that noticeable. You have to be very vigilant with sun care after you have laser.