Fairly broad topic and "favorite" has a lot of factors. Some have a fun tied to sentimental value, some have tight budgets which limits which ones they own and some have different frames and sizes which makes one better to them then others. None of that makes 1 gun better then another, just means that's the gun that fits that person and they have the most confidence in.
My own personal preference after owning a TON of shotguns is the benelli M2 20 gauge is my overall favorite when it comes to turkey, dove and just fun shooting with the benelli SBE2 a close 2nd.
Just absolutely love the fit, feel and quality of those 2 guns! There are a lot of great/good shotguns out there though just depends what you want and what you can afford.
My least favorite personal options (guns I wouldn't own if they were free) are the 835 and the Nova. Again just my personal opinion. Sure both shoot and either will kill piles of turkeys but man I have never found a poor rattling POS shotgun then those 2
(no personal attacks where made against anyone that has one and disagrees with that statement)