They suck. I've flown in a Cessna with a touchscreen transponder, and it was nearly impossible to enter the required four-number code in light turbulence.
edit: That said, you could probably make a decent aviation touchscreen. The main issue with off-the-shelf screens is it's easy to brush the wrong thing. A screen that takes significant pressure to register a touch would probably be usable, and for all I know this system might do that.
edit: That said, you could probably make a decent aviation touchscreen. The main issue with off-the-shelf screens is it's easy to brush the wrong thing. A screen that takes significant pressure to register a touch would probably be usable, and for all I know this system might do that.