Damage isn't what kills Jedi/Sith. Interrupting swing-block is what kills Jedi/Sith. P3 is the least comfortable gun to use vs Jedi/Sith. If you miss a shot, or they weave, you are going to die. The rate of fire very nearly matches swing-blocking a yellow combo. If you interrupt one slash with P3, the subsequent yellow swing will probably take you. In the worst-case scenario you will be cancelling each other out until one makes a mistake. It is a lot harder to miss with a lightsaber than a gun. For a gun with a low rate of fire and high base damage, the FP drain isn't anything spectacular. If you shoot a Jedi/Sith unaware that they have deflect, you will probably do a trivial amount of FP damage, whilst taking a huge chunk of your own health. Balancing saber versus gun really lies at the intersection between a class's mobility/Force immunity and the guns it is allowed to select from. If I am to consider the gun in isolation, then yes, against a gunner P3 is exceptional, but against a saber it is inadequate.