My experience is that the new FilteControl loads do best through a CYL or ImpCyl choke. 'Standard' loads will differ from gun to gun in how they perform, as a rule many tend to do well with a Mod choke, especially the reduced recoil loads with buffering, hard and/or plated pellets and shot cups. The cheap stuff (S&B, Rio etc) with soft lead pellets and little or no protection for the pellets, tends to throw open patterns no matter what.
Bottom line is, it's OK to shoot buckshot through a Mod choke, but you won't know what kind of patterns you'll get until you test some different loads and see.