I know you're wanting a 3 1/2" 12 ga semi-auto for turkey hunting as you stated. I carried a 12 ga 3 1/2" for years for turkey but now only use it for waterfowl. For the past 3 years I've carried a 20 ga (3" chamber) Remmy 870 youth model. I topped it with a Cabelas multi-reticle scope. With #5 Winchester ammo it is deadly on turkey out to 30 yds with an extra full choke. And this is a joy to carry (almost like carrying a BB gun).
Have you considered looking at the Benellis. They make a few excellent semis in 3 1/2".