I use a metal filter disc now but have always used the inverted method whether paper or metal, I never quite understood the “normal” method as I’d assumed you’d lose half the tube into your mug before you got the plunger in!
I don’t see how the metal would be any better / worse than the paper discs in either method to be honest. So in short, I don’t know, have no experience of your method, but recommend you go inverted!
Notter, “Coffee Hipster” 🙂