Mercury specifications call for 5250 to 5750rpm WOT. I guess anywhere in there is ok. If Joe is fishin out of Miami the throttle won't be pushed to the corner much anyway. The Mirage really has a lot of bite. I would try a different prop because I would be concerned with lugging the motor under a heavy load. (Boat full of gear, four guys, 200 lbs of dolphin and a couple wahoo) If it launches, Mercury said it is ok and more importantly Joe is happy, well jam up happy day.
