Accuracy, lead, etc. are far more important than what choke you use. We are really splitting hairs when we start comparing Mod with LM or IM. Heck, there is a greater difference in choke constriction between the various brands of guns and chokes. With lead shot if you shoot something like IC or Mod you will be just fine. As a general rule, if you shoot steel you should use a little more open choke. I'm sure that over 90% of the guys in the field have never patterned a gun and never will. Hell, when I was a kid in the 50's and 60's we were just glad to have a functioning shotgun and a few shells regardless of how the gun was choked and what size shot was in the shells. 