We go through probably at least 500 rounds per year night hunting coyotes there's something to be said for brass that processes easy especially when I have to load it all. And yes that WSSM brass is heavy. It trims hard, it sizes hard but I will admit it is a beastly round but I don't want to have to deal with it in great volumes.
I realize this thread is about the fastest 22-caliber but I swear up and down you can't beat the 6x6.8 shooting 70s if you don't want to fire form. The 6 DTI would be a great option to with the shilen barrel but I I don't see any other advantage until you fire form, and then you're probably still not going to shoot a different load than what you shot to fire form. The Shilen blank is the only advantage I see for someone who shoots anything other than a minimum volume of ammo like say maybe for deer hunting.