There are many CO2 lasers in the market and each with their own proposed form of individual technology. Some even combine with other modalities such as radio-frequency and report synergistic results.
The specifics of the above considerations are something that we as doctors take when purchasing the machine, and, I would say, is not something you as a patient should be too concerned with; what matters most is the operator's experience with lasers in general, as well as with the machine he/she has in his/her clinic - being able to manipulate the machine correctly is most important to ensure results are optimised while side effects are minimised.
More importantly, scars typically require a mixture of techniques for optimal outcome, and this means more than just using "the best" CO2 laser in the market. Some patients require minor dermatological surgeries like subcision with or without fillers, and others TCA Cross for pitted scars - something CO2 lasers, regardless of worth, will not be able to treat sufficiently well without first causing major side effects.
It would be best for you to discuss with your doctor your current issues and needs before committing to a procedure.
