New today to the forum. Picked up my FNS-9 full size today and discovered it was manufactured in 2013. APEX Tactical notes that their trigger is not compatible with pistols manufactured prior to 2014. Does anyone know why? I know the pistol was sent in for service to clear the issue related to accidental discharge (out of battery), an issue having to do with the striker. but I don't think that would prevent installing the APEX trigger. I found an old post that it has something to do with the shape of the trigger bar? If so, what should I do? Any info is appreciated.