I had PRK just over a year ago. It is the only surgery currently allowed by the Navy. Both Lasik and PRK reshape the cornea in order to restore 20/20 +/- vision. However, PRK surgery forms the cornea entirely through surface ablations while Lasik requires a flap cut in the cornea and the reforming work done underneath this surface layer. The cornea flap in the Lasik procedure acts as a natural bandage reducing infection risk, pain, excessive scar tissue build up, recovery time, and as a consequence--$$$--because it takes less time and supplies for the opthomologist to care for the Lasik patient. That's why lasik is the more common pocedure. PRK IS more expensive. But the 'flap' may be a detriment under stressful situations--such as high g's.
PRK is a solid procedure, but you gotta adhere to the post-op guidelines...scar tissue and infection risks can adversely affect your recovery.
That's my double penny's worth.