I have the MB's with KBS tour shafts and love them. But do note they are a heavier shaft and caused the swing weight to be a C9, I had to use quite a bit of led tape IOT get them back to a D2. Yet if you want a lower ball flight I would go with the project X rifled shafts. Thats what I had in my 710 CB's and it lowered the ball flight quite a bit. Im sure whom ever is fitting you will be able to point you in the right dirrection. Just keep in mind that change the shafts most likely will change your swing weight.
Dave, i am currently a 7 handicap and play the 712 ap2's which are 2 degrees upright, and half an inch long. I really love these clubs. If you are coming from game improvement irons i would not go directly to the mb's becasue the change will be drastic and very hard to get used to. The 712 ap2's are a great combination of workability and forgiveness. They are suprisingly easy to hit for a forged iron. I have also hit the mb's numerous times and i found them to be slightly lighter than the ap2's, but they are not that much different than the ap2's, they are very easy to hit just like the ap2's, and to be honest if your split on which one to get, go get fitted and hit them both a lot to really find which one will help you the most. your Welcome! Johnny