If you gotta have the 3.5" and you got $1200 to drop I'd go with the Benelli Super Black Eagle II... A friend has one and its a dream, I however only have a lowly Benelli Nova.
For a dirt cheap Semi-Auto get the Saiga-12 or Saiga-20, autoloader built on an AK reciever in russia.. $300-$400 out the door. My Saiga-20 is my favorite gun of all time... its a f***ing blast to shoot clays, phonebooks or abandoned cars with, but might not be up to the long-range bird hunting you do....