I used the same gun last season. There is no difference between using the 725 versus any other gun with walnut and blueing, exept for the third shot with a semiauto. I purchased waterfowl choke tubes from Carlson's and used various ammo. Most of the time I used 2 3/4 shells since I was hunting over decoys. Never had a problem with cripples.
I prefer over unders and didnt miss the third shot. The main disadvantage is trying to break open the barrel in field pit blinds. That can be awkward. Other than that, there is no disadvantage and it is a matter of preference.
If you like the gun and shoot well with it, use it. That being said, I wouldn't use it in saltwater. When I fly to the gulf coast I use my SX3.