What is the best shot size and what chokes should I use in my stoeger o/u 12 ga?

I use a 12g winchester super full choke with 3inch mag 6 shot.

I have a Winchester Supreme o/u 12 ga.....i use full and modified chokes...top full bottom modified..with 3 inch #5 or #6 shot..#4's are ok but not as many pellets out there...

If they are decoying I would use 7 1/2 trap loads and mod and full .
If they are not decoying good I would shoot a fast 1 1/4 oz load of 6 with mod and full or full and full.
My load for that stuff is a 1 1/4 oz of 6 in a Fed gold medal case using Longshot Powder at 1440 fps (Hodgdon)

when i am hunting in woods and not feilds i use the cheap 6 or 7 shot with a mod. choke. but when i am in the open feilds where shots can be long i like the faster loads in 5 or 6 shot with a full choke.