I've got the Grey Oakley lenses and they're fine. They have the same transmission profile as the Black Iridiums but let about twice the light in. Cruising along in the tops, when it's ridiculously bright, there is no perfect solution, I turn the EFIS tubes up to their brightest setting and they're still readable, but I wouldn't want any less tint, cause it's still really bright out. I think the Grey is a good happy medium. Never have to squint underneath them, but miss them when they're gone.
As for wearing them under a headset, it's very difficult to wear any pair truly "under" the headest, with the earcups clamped over the frames. Even if the frame is very thin metal, they'll be bowed in against your head which does wacky things to the lenses and the nose brace. What I and every other Oakley wearer I've seen do is simply slide the straight frame over the top of the earcup. This cants the lenses down just a few degrees but avoids all head clamping sensations, and ya get used to it within a minute. No pain.
