When I bought my 682 Gold E combo, it came with 6 choke tubes. Two of them were IM. I used them interchangeably and ran hot an cold. One day, after a particularly bad couple of rounds I complained to a friend and was told to put a different choke tube in. I put in a full and ran the next 25.
The next day I went to the range, set up on a bench and shot each choke tube in each barrel for POI. I found that only 2 of the 6 choke tubes shot within 2" of each other at 20 yards (one IM and the F). The others were all over the place. I also found that all three barrels shot to different POIs with the same choke tube.
As set of Briley choke tubes cured the differences between choke tubes, but I still had the problem with the barrels. So I eventually sold the gun.
Most Beretta and Brownings have that problem, and others as well, I'm sure. That is precisely why I choose to shoot fixed chokes for trap.