I won't give up my 26 incher on my 870
Nitro company testing confirms this:
The modern turkey hunter sacrifices pattern performance and velocity for maneuverability of a short 21" barrel. A gun with a 26" barrel will give you higher velocity and better patterns. For every inch up to 26", you gain 7 1/2 to 15 feet per second in velocity, depending upon the gun. A 26" barrel will give you 10 to 15 percent better patterns than a short barrel with the same choke constriction.