[kartu]

Mark, code could check for model in:

Core.config.model

or:

System.applyEnvironment("[prspModel]")

It would be cleaner, however, to check for something like "hasTouchScreen". I'll add it to "compat", it will be defined and set to true only for models with touchscreen. So:

Core.config.compat.hasTouchScreen

PS
Just came to my mind, that "hasNumericButtons" is already there and could be used instead of "hasTouchScreen" with negation.

Long story short: Core.config.compat.hasNumericButtons is set to true on 505/300, and will be set to false on all touch devices.
I doubt we'd ever see reader with numeric buttons and a touchscreen.