Fair enough, I prefer the Double Bronzers cause I can sink any ship in the game in 2-3 volleys whether I cause a special effect or not.
I actually found one ship (I think it is a Magran worshiper one) that had what I feel may be the best gun in the game. Some sort of fire cannon that only did two less damage than a double bronzer, but reloaded in 4 rounds. It also had an optimum range of 0-400, meaning your enemy can never be so close you are out of optimum range.
I don't know if you can actually get one for yourself though :/. There is one gun arguably better though, good old Haefric's Nose. 200-600 meter range, equal damage to a double, 4 round reload. That's a gun!
Wyrmtongue cannons are the fire cannons that have 0-400 range, they're pretty awesome.