I only have one shotgun that takes screw in chokes and its a 390 when I bought it it had a briley extended smothing choke in it, the guy I got it from was and still is a blackcloud fan boy. I payed 50 bucks for the gun, he said the gun was no more good lol. I bought a carlsons extended full and shot several diffrent shells to find the one it likes the best and that turned out to be the fioochi 1 1/5 #2.
I have one other choke for it and that is a drakekiller choke I had built for the barrel to use on snow goose hunts.
I dont use this gun as much as my older guns, my A5 magduck and my 870 wingmaster mag both fixed full chokes.
whatever choke you go with like others have said take the time and pattern it with every shell and shot size yoy think you might hunt with and find the one it will pattern the best.