If you are going to be waterfowl hunting out of a blind, I don't recommend it. An O/U has to break too far over to reload the bottom barrel, making it cumbersome in an awful lot of blinds. I know someone is going to say it's no problem, they do it, and I know you can do it, but I have a friend who loves O/Us, owns one of the very few Krieghoff Royal Crown 4 barrels sets in existence, and a couple of Perazzis, and all kinds of others, but he went to an 11-87 or an 870 many years ago for waterfowl for that very reason.
For dove, take your pick. I don't like any O/Us much at all, but a 28 gauge Beretta tempted me once. Beretta does make some nice guns.