Depends on a number of things. What kind of birds are you going after? What type of shot will you be using? What distances are you planning on shooting? For average upland bird hunting at 30 yards or so Mod or Imp is just find. Make sure if you are shooting steel shot that your choke is approved for steel. If you are shooting farther than 30 yards or using them for turkeys, snow geese or any waterfowl you may want to look into aftermarket chokes ie: Wad Wizard, Patternmaster, Kicks.