Vizplex isn't inherently limited to 4 shades, the current crop of
controllers only does 4 shades. I guess Vizplex caught the display driver designers napping.
The six inch screens are plastic fronted ... I don't know about the backplanes though. I believe the iLiad has a glass front because of it's wacom panel, to allow for the stylus friction, I mean. In any case, my 12.1 inch tablet screen
is glass fronted, and seems to have no problem with fragility, so I'm not sure that's the hold up.