I had this done a few years ago and found it was well worth it. I had 2 treatments done and my sun spots completely disappeared. After looking at my before and after shots, I couldn't believe I lived with them for so long. I just had it done recently and I will continue doing it each year for maintenance.
I do use Obagi products as well which I firmly believe adds to the longevity of no more brown spots. The spots do turn a bit darker when first done but just flake off. Mine took about 10 days to completely disappear. I would recommend this for anyone who wants their brown spots gone.