I've been switching back and forth for a few days now between not having the screens (still original plastic grills) and having them. If I don't have them on I've nothing to replace them with so I just screw the driver down with some screws of smaller length, put the pads on and listen. However, because the screen is absesent there isn't any backing for the pads (i restuffed mine so that they are much plusher) to push on, thus my ears hit the electrostatic drivers. With the screens this is fixed, my ears are a comfortable distance away and the sound is much more spacious as I'm not right against the drivers. So far tho, I've not noticed a huge difference in sound quality with the screens on or off, sounds pretty much the same to me. I'll still rescreen them i guess, but has anyone really noticed a marginal sound difference between having the plastic screens and not having them?