Why don't more folks use O/Us for turkey hunting? There are several reasons with cost being the primary reason. Most decent quality O/Us are gonna run over $1k for starters. That is well above most shotguns used in the turkey woods. Another factor is there aren't that many full camo O/Us on the market. Another is 3.5" guns, Browning only built a 3.5" Citori with camo and Duratouch for about 1-2 years. Of the big makers, I don't know anyone else that builds a similar rig. The cheap imported crap from Turkey and parts wherever are just that, CHEAP CRAP. If you have ever hunted/owned a Citori or Onyx you can feel the crap like the new Mossberg O/U with only picking it up once.

Another reason is tubes. The vast majority of turkey tubes on the market are extended and many are ported. Other than a handful of competition chokes (like the Midas system from Browning) extended tubes are not an option for O/Us and sidebys. I suppose you could just put one in one barrel and go full with the other but that seems a lil silly too me. Another factor is weight. You are carrying around 2 barrels and a heavy reciever, especially if you DO have one of those 3.5" O/Us. And if you want a red dot scope on the setup you are about out of luck unless you go with a less than preferable (and unsightly) rib mount bracket.

With regards too the selectors, Browning, Beretta and Remingtons O/Us all feature the barrel selector built into the safety. You get used to that after a time or two out with the gun. I occasionally use my Citori Special Steel for ducks and the ol gal has fixed tubes so I must switch "on the fly" or as the birds are coming into the dekes. But I have had the gun for many years and it is second nature.

Nope for a turkey gun I want a FULL BOAT powered pump or auto. I have used many of my shotguns for turkeys on my annual trip too southern MO. But NONE of them (including my 870 Supermag) can stack up too my ol 835 UltiMag with a Rhino tube, a 45mm red dot and 2.25ozs of Nitro triplex loads!!!
RA

ps
Another point I forgot to make is that with multiple barrels you must sacrifice something and that is exact pointing. I forget the exact yardage but most high quality O/Us are made to "cross paths" at a given distance (I want to say something like 30yds or so but honestly can't remember). That means that the center of your pattern isn't going to be precise with that kind of gun. Not something to be concerned with while wing shooting. But if you are a real pattern fanatic for turkeys you will be bothered by that!