I have been using the same Wilson trimmer for over 50 years. Not very fast, but ultra precise. I trim all handgun brass of the same caliber to a uniform length. If you are after ultimate accuracy, that will require uniform crimps and that is obtained by cartridge cases of the same length with square case mouths. If you are just going bang, bang, bang, then it isn't worth the bother.
Nobody will ever learn to shoot very well, with mediocre or slap dash ammo. A shooter, must know if where the rounds land are the fault of the ammo or the shooter.