If you are going to buy new, you are going to need to spend some money to make the guns work for you when you're on the clock. Typically new guns are stiff and slow. Used guns can use some work, but they are at least past the "stiff" point.
On the new gun, dry-fire it, then with one hand move the lever and open the gun. You probably can't do it with one hand, because everything is tight and stiff, you are cocking both barrels, the springs are new and strong, and if it is a coach gun there isn't any out front weight to assist you. A gunsmith will cost $100-150 to smooth out everything and lighten or install lighter springs.
With a 28/30" barrelled gun, a flick of the wrist and the gun should open, even when it is new. A good used gun will be Half the price of new, and should be useable without any serious expense. Lightening and polishing the workings are simply icing on the cake. Besides, with a good used gun, you can buy a long barrelled beast, try it, and shorten it to your liking. I still maintain that 24" is a nice balance between a coach gun and a long gun.
Just my 2 cents worth.
JB
Thunder Bay