Different areas of the body heal at different rates so it would depend where the scar is.
The face heals more quickly than other body areas and if your scar is located on your face you might want to "take the hit" and opt for the Fraxel Repair. You will have some downtime and you likely will not be able to completely remove the scar. I've had excellent results on isolated injury scars on the face with the Repair, but even with this laser, it takes more than one session.
For scars on the body I'd recommend the Fraxel Restore because the healing time and complication risk is much smaller. You will need more treatments since you are using a different laser.
I also assume you are referring to mature scars and not just redness left from a recent surgery. If the scar is new, the improvement will be better if it's treated earlier.
For scars that are not that noticeable except for redness, you could have treatment with a vascular laser to reduce the redness.
