If you look at some of the choke diameters online from manufacturers that make chokes for both the SBEII, and Beretta Extrema 2, it seems that for some of the chokes in the same constriction, the diameters are different. For example, go to carlson's choke tube websight. A Benelli modified Crio Plus tube is listed at .705. The Beretta modified Optima Plus tube is listed at.713. Which equates to about 1 step in tube constriction differences. An Optima Plus full is .703. The dimensions and threads are the same, but the exit diameters are different. This may not be true for all chokes that fit both these guns. That being said, I have a Briley Dove Duster(light modified) choke for the beretta Optima Plus syster, that I shoot in MY SBE II. Have been doing so for about 3 years, and it's deadly on clays, doves, and early season geese. So, I guess it could be like shooting an improved cylinder in My benelli, since the optima plus tubes are a bit larger in exit diameter, for the same labeled constriction. Does that make sense? With the more open chokes I don't think it would be a problem. But if you had a full in the beretta optima plus tube, and put it in the benelli, it could theoretically be even tighter(extrafull), and that may potentially be a problem.