I have used Pearl for several years and find it excellent for skin discoloration. One treament gives dramatic results.
Fractional CO2 (I am familair with and have used Repair, Active Deep FX and Juvia) give excellent discoloration improvement also but more skin tightening than Pearl. Downtime is longer and they hurt more than Pearl.
In general I'd say Pearl great for 30-45 year olds, Juvia for 40-55 year olds and Active Deep FX and Repair best for 40-70 year olds.
Hope that helps.