I've used Hevi-Shot (Tungsten) since about 2002. Very lethal stuff.
Having shot my first duck about 1965 or so, I have used lead, steel and now Hevi-Shot. In my experience, HS is noticeably better than same size lead, so I step down one shot size from lead. HS 6 will kill Mallards very well out to about 45yds, and when using HS 4's, it usually penetrates through Mallards at 45yds, and kills geese in excess of 50yds cleanly.
When I run out of HS, I'll try some ITX shot from Ballistic Products.
