6' here, and the PO changed the screen, not sure what but it isn't stock.
30-70mph, screen fully up, and there's so little wind that I usually have either my visor full up, or the chin bar up (flip helmet). I can still talk on the phone without folk even knowing I'm riding.
Below 30, I tend to put the screen down, but that's because it's a lightly smoked screen, and seeing through it close to the bike is a PITA.
Motorways, the screen is usually half way, because the wind from large vehicles bounces the bike around, and I don't want to have to deal with wind catching the screen at the same time.
At some point I'll look to change the screen, but mostly because it's lightly smoked, and terrible to see through when slightly dirty (and before the "clean your bike then" comments... I commute, it can be clean in a morning, and have splash marks etc all over it by the evening).