This perk instantly raises all SPECIAL attributes to 9, but will not lower attributes which are already at 10. If already having collected the bobblehead for an attribute before taking this perk and the attribute is below 10, it becomes impossible to raise it to 10 by normal means. On the other hand, if choosing this and then find a bobblehead, the attribute will be raised to 10.
Having the Lucky 8 ball in the inventory upon taking this perk, Luck will decrease to 8 when the ball is removed from inventory. If one plans on getting this perk and have the Lucky 8-ball, be sure to leave it someplace safe until after getting this perk, then pick it back up and Luck will still be 10.
If, from the moment of starting the game, it is planned to get this perk, one should not acquire the bobbleheads for the S.P.E.C.I.A.L. stats until raising those stats to 9.
However, there are 'work-arounds' for bobbleheads, such as the Luck bobblehead, which can be taken early if picked up the Lucky 8 ball after taking 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 intended 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.