I agree with Dr Justin that a combination treatment approach is preferred in treating acne scars. Most patients have a mix of different scar types that will benefit from subcision and energy based devices.
The latest Fraxel platform is the Fraxel:Dual which combines the Erbium Glass wavelength in the older Fraxel:Restore (same as Mosaic) with a Fractional Thulium (aka BB laser/Lavieen/LaseMD). The Thulium wavelength actually helps with reducing epidermal pigmentation too, apart from resurfacing scars and uneven texture. Qswitch or Picosecond lasers are still needed to achiever faster results with dermal pigmentation.
Fractional CO2 remains the gold standard in acne scar treatment and I use it selectively and in combination with the above two described wavelengths. I also use the fractional picosecond technology to treat acne scars – this is a whole new dimension of acne scar treatments and has shown promise of treating certain scars better than the fractional CO2.
A proper consultation and communication with your doctor is key to successful treatment.