RE: mod. choke
I shoot a Nova, and I personaly like an improved cylinder choke out to about 30 yards with #2's. If the ducks seem to flying in a plateu a little higher up, I switch to my modified. You know your shooting ability beter than anyones else. I believe that you should patern your gun and go with what suits you best. If you can hit them consistantly with the tighter paterns @ 20-25 yards, shoot it, that way you can extend your range a little without making any changes.