It's about how the gun balances in your hand. If you're shooting using both hands to operate the gun the bbl length is less important as you are holding the gun with two hands and have a lot more control over it. A long bbl gun held in two hands would not necessarily feel muzzle heavy. Also using two hands would mitigate recoil making for a faster operation. A short bbl gun should balance better for a duelist. The better a gun balances the easier it is to aim, cock, fire and recover from the recoil. Of course, all of this assumes that you are going to shoot a caliber and a load that creates recoil. If you are shooting mousefart loads with no recoil then it's just esthetics. Shoot what appeals to you. And as I've said on other threads, a shorter bbled firearm is generally faster than a longer bbled firearm. My personal preference is a 24 in rifle, a just barely legal pump sg and 4.5 bbl SAs or 5.5 or 6 inch DAs. Have fun, don't spend any money until you try it out if possible. See what works for you. It's a great sport, enjoy.