This perk instantly raises all SPECIAL attributes to 9, but will not lower attributes which are already at 10. If you have already collected the bobblehead for an attribute before you take this perk and the attribute is below 10, you will be unable to raise it to 10. On the other hand, if you choose this and then find the bobblehead, the attribute will be raised to 10. If you plan on getting this perk and have the Lucky 8-ball, be sure to leave it someplace safe until after getting this perk, then put it back in your inventory and you'll have 10 Luck.
If, from the moment you start the game, you plan to get this perk, it is advised to not acquire the bobbleheads for the S.P.E.C.I.A.L. stats until you raise those stats to 9.
However, there are 'work-arounds' for bobbleheads, such as the Luck bobblehead, which can be taken early if you pick up the Lucky 8 ball after you take the perk. The Strength or Perception bobbleheads can also be worked around when doing the Those!quest correctly for the Ant Sight or Ant Might perks. Also, any S.P.E.C.I.A.L. stat that is already at 9 can be upped prior to receiving this perk without risk. This is especially handy if you intend to destroy Megaton, as that is where the Strength bobblehead is found.
With this perk and enough skill books or high intelligence, it is possible to obtain perfect stats.
If you have the Lucky 8 ball in your inventory when you get the perk, your Luck will decrease to 8 when the ball is removed from your inventory.