Back on topic - I have no problems with blackpowder guns in my campaign (Forgotten Realms). It is extremely expensive and generally not worth it. Only the gnome has a pistol and no one else has even asked to buy one. Overall the guns are not that powerful, expensive cost, 1 feat to use effectively, can't get wet, and cannot apply strength modifier to damage.
I did give the party several barrels of blackpowder for use in destroying a Temple of Bane but it backfired when the NPC fireballed the wagon and the resulting explosion killed 2 players and knocked 2 unconscious. But that is another story.


