I agree with Samilspec - in the sense that I'm just one of the hunters in the field ....... he's doing the calling, working the dog, worrying about some newbie's handling a gun for the first time .... and all I'm doing is shooting and having a great time - and admiring a good caller and dog handler in action ...(both skills I don't have ..).
( I don't camo my O/U for duck hunting ..) - the gun is out of sight until the guide yells for us to "take em" .....
When I had a bird dog / for upland birds not waterfowl - I would usually leave my gun in the truck - let the kids shoot and all I did was work my dog - but a guide doesn't have that option. Paying customers are an interesting lot ... some are serious shooters, accomplished clay target shooters, accomplished bird hunters ......and some are so hung over from partying the nite before they can't see, some have no idea what a mallard drake in flight looks like vs a hen and bust anything that flys, some cripple more birds than they kill requiring the guide to do a lot of clean up, and don't get me started on gun handling skills around newbies ( makes me flinch ....).
I would probably go with a synthetic stocked semi-auto or a good pump gun if I were a guide.