What are the risks of a hairline advancement surgery vs a hair transplant lowering surgery?

The main reason to get a hair transplant lowering procedures are (1) there is no limit to how far to lower it as it does not require a loose scalp (2) the hair transplant lowering will address the sides of the hairline (the temple areas) which can be built up to create a rounded look which can not be accomplished with a hairline advancement surgery, (3) there is no risk of frontal scarring with the hairline lowering transplant approach as with a hairline advancement surgery and lastly, (4) if a general anesthetic is used for a hairline advancement surgery, the risks of general anesthesia are greater than the risks of a local as with a hair transplant lowering procedure.