skandar

Just picked up an M3 with the standard 5 round mag. As far as I can tell, my only option for a mag extension is SRM. Anyone have bad experiences with them? It still has the pre-97 rear sight housing (though Benelli says the S/N indicates '99 manufacture) . If I get the new LPA style sight will the new housing mounting points match or will I need to get filling / drilling / tapping done? Thanks in advance.