Huntsalotey

I am new to shotgunning. I have had two shotguns in my lifetime. I had a .410 that my dad got me when I was young and still have put away till my 3 year old boy gets ready. I had a 12 ga. Eastfield model 916 that Dad got me for my 13th birthday. No longer have it.
Well I wanted to get a new shotgun for all around shooting and shotgunning and to use for Turkey hunting. Not primarily a Turkey gun, but one I could use. I wanted it to be accurate and hold tight patterns. Being new to shotguns I did not have any experience to draw from. I went to my dealer and looked used. He had 1 870 Rem express in 12 ga. with 28 inch barrel. The receiver and barrel looked good but the stock and forearm was wore pretty good. It would have to be redone on the wood to look good. He had 1 Winchester 1300 12 ga. with 28 inch barrel. It was the Ranger model. The wood looked good on it, but the receiver and barrel was rusted. Not completely but a considerable amount. He said you could get it off with oil and steel wool but to keep it off you would have to re blue it. And he had 1 Mossberg model 835 ulti-mag 12 ga. with 28 inch barrel and the barrel was ported and overbored, whatever that means. It looked brand new. If you held it beside a new one you could not tell it apart. Even the ejection port metal that is silver was still brightly polished and silver with no spotting. It has the Accu-Mag choke.
The Remington was 219.00 The Winchester was 175.00 and the Mossberg was 199.00. Of course that was priced to me. The tickets were more. Anyways I choose the Mossberg. It had the ventilated rib also and he said the ported barrel would cut down on recoil. Do you think I made a wise choice based on the 3 shotguns? Again I have no shotgun experience.
Also, what is the Accu-Mag choke? Is it full or what? Would it be fine for Turkey hunting? Thanks
Whitey