Hi, Does anybody know the differences between the FN 5.7 IOM and The USG models? Any help would be  greatly appreciated! Thanks,

Really not much besides the trigger guard. They are both single action only. They both have adjustable target sights and the picatinney rail in front. They both have a magazine disconnect safety.

The real difference is the trigger guard. IOM has the double circle arctic trigger guard and USG has the squared off one. The grip on the IOM has little round bumps. The USG has spikes.

It's basically the same gun with different cosmetics.

Boofus, Thanks, do you know if the 5.7 has a trigger reset similar to the glock??