For that type of money I'd personally stay away from a 3.5" semi auto. I am sure their will be stroeger, mossberg, etc fans telling you otherwise so just my opinion. I have a benelli nova pump 3.5" and really like, functioned flawlessly with all loads. It maybe weird looking but don't judge it until he throws it up, I thought the same until i shouldered and swung mine...then I bought it!!
Since we don't have turkey's I now see little need for 3.5" for waterfowl (however i don't pass shoot either just over coys). Could also look at the Browning BPS, Rem 870, etc.