I have experience with everything under the sun for shotguns. I own an 8.5, 12.5, 14 , 18 " barrel shotguns with standard stocks to pistol grip only stocks.
8.5 your limited to 2+1 or maybe 3+1 if your lucky.
12.5 short and easy to move and 4+1
14" with a +1 extension 5+1 rounds (my personal favorite for CQC)
I have an 18" top folder which is my main hiking shotgun. I like being able to have it in my shotgun scabbard on the side of the pack which allows quick access and my hands are free when hiking. Falling on my face is more likely to happen than meeting a deadly encounter, be it a zombie , bear, cougar, wolf, or other human who has bad intentions.
Top folder allows for easy carry, when folded I can move through trails and brush without getting the stock hung up.
If I need it and time permits I can open the stock in a matter of seconds and then I have a full stock shotgun. Really if I get jumped by a zombie wearing a bear suit I'm likely not going to have a great deal of time to open the stock or even shoulder it for an aimed shot. In all likelihood I'm going to be firing from the hip or low ready position anyway.
With practice, and that's the key. ... I can hit a 4l milk jug with slugs at 10 yards with a pistol grip shotgun. Does the recoil suck, yup but that's the cost of doing business.
Any and all configurations have their purpose and usefulness. It's finding what your needs are and then training to ensure you can meet those needs. Just because I jump behind the wheel of a Ferrari doesn't mean it's going to drive itself. Your the operator and need to learn it and train it. It's just that simple.
My hiking set up
At this time I had a knoxx pistol grip on it.