if they've been around since 1991 and aren't yet in every gizmo imaginable, then there must be something wrong with them, and that's why the price hasn't come down
imho that switch looks huge - despite the novelity of having a minature lcd display with a custom color backlight, why would anyone make a design using a huge button like that. I wonder how the glass in the LCD holds up to the rigors of being poked day in and day out
I'm not sure you need to be refreshing the LCD, I think they use some sort of serial interface, so you send it new data when needed, and the onboard circuits handle the bare glass interface.
I think these switches are made largely obsolete by resistive / capacitve graphical touchscreen LCDs