It makes a difference, yes.
The normal state of armed violence in Apocalypse World is 3-harm vs 1-armor. You can view this as a breakpoint in the system. The gunlugger, the chopper, and the battlebabe have access to armaments that put them on the other side of the breakpoint: at 2-armor vs their enemies' 3-harm, and/or at 4-harm vs their enemies' 1-armor. This mechanically changes their relationship with violence.
Balance isn't a big deal in Apocalypse World. By session 3 or whenever, the players and their characters have trampled all over the game's starting balance and it's in ruins. But as far as that starting balance goes, yes, the better guns are a component.
-Vincent