Agree with all the above!
some questions might at least focus things..
How far do you hit the 913 currently?
What shaft is currently in the 913?
Were you fitted for the current shaft?
Why are you considering changing the current shaft?
What are you trying to achieve with the new shaft?
What sort of price range are you considering?
And as the 913 is an adjustable driver - so shafts with the appropriate adapter can be simply swapped, in and out - why haven't you simply test-driven a load of shafts already?
