Here's what you should be taking note of when you're in the market for a new shotgun
Screw-In Chokes: Allow you to switch chokes easily depending on the activity.
Quality of Metal Finish: Depth and evenness of bluing with sharp definition of corners and other sculpting.
Ventilated Rib: On shotguns, a ventilated rib provides a straight sighting plane and also allows the barrels to cool more quickly.
Balance: The feeling of quickness and evenness of weight distribution in the hands.
Action Smoothness: Overall slickness and ease of operation.
Safety/Barrel Selector: Should be easy to distinguish between the "fire" and "safe" positions. Safety should lock positively into position.
Checkering: Look for the depth, sharpness, evenness and design of the pattern. Generally, the greater the number of lines per inch, the more desirable the checkering job.
Trigger Geometry: The comfort and efficiency of the shape and angle of the trigger as related to the hand position on the grip of the stock.