I have had a series of 5 Fraxel treatments for treating acne scarring over the last 12 months. I am very happy with the results I have gotten thus far -- my red scarring has been minimized greatly and my skin is much smoother and healthier looking. Full effect really cannot be seen for about 6 months after your last treatment, so you need to be patient.
Improvement on some icepick and rolling scars has not been as good but has improved somewhat. Most of my scarring is of the red mark variety so I have noticed improvement -- YMMV.
The pain is pretty uncomfortable to severe -- they put a numbing cream on for an hour beforehand, which definitely helps .. if you are quite sensitive to pain, get the painkillers, but you will need to have someone drive you then. I have very pale skin -- I am not sure if that has helped with the treatment or not, as some with darker complexions seem to have experienced more negative results. All in all, I am pleased with the results but it is a little pricey.
Downtime is about 2-3 days of looking puffy in my experience .. so don't have any major social events planned for at least 4-5 days out.