No, it doesn't depend on the pilot.
ack-ack
The B25C is about half and half Ack-Ack, I can make the old girl do some pretty wild maneuvers but in the end I'm never going to out fly a fighter that has half a brain. The B25C only has 2 attacks in a dogfight, ho and lucky top turret shot. Otherwise the plane is to slow to do anything.
And on the F3 shooting thing, I use F3 view help my SA while I'm flying a B25 as a dogfighter, however, whenever I think I may have a shot coming up I switch to F1 and use the crosshairs to fire. I don't use F3 to actually shoot because I never hit anything and in a B25 you get very few chances to take a shot so I always use a gunsight.
People that are good at shooting in F3...well...more power to them, but don't assume every bomber pilot uses F3 to shoot.