I haven't even seen Tungsten shot in Qld, Australia... I'd love to try it out, however, I cringe at the thought of how much it would cost!!!
The density of the shot sounds like good news.
Like others I suspect I will be sticking with lead shot, and hard cast projectiles I can manufacture myself, after all, given how little shot the .410 uses with each reload it will take me a while to work my way through what I have now!