All my shotgunning is done with semi autos. Same goes for my group of hunting buddies. We own more than fifteen different models between us. A 3" chamber is more than enough but, the 3 1/2" is great as well. I like synthetic or better yet the camo ones for hunting except for upland. I'll list some models that I recommend in a few different groups.

3 1/2" models $900.00 and up. Beretta Xtrema, Benelli SBE's, and Browning Gold
3 1/2" models under $900.00. Franchi 912 and Winchester SX2.
3" models $700.00 and up. Beretta AL391, Benelli M1/M2, Browning Gold's.
3" models under $700.00. Beretta's 390,3901,Pintail/ES100, Franchi 612, Weatherby SAS, and Winchester SX2.

All of these models have good quality, many features, and are very reliable. They each have their own strengths and weakness. Most of the above models are owned by someone in the group. Any of them would make a great choice for a turkey gun.