Really need an update to work better for what the are advertised for. The center piece needs to be designed to properly allow multiple insertion and removal without breaking, and the tolerances on the outer shell need to be widened so keycap and switch pullers can fit.
If you can't use it as a proper tester, then advertise as a fidget toy. If you want it to be both, make one that will work as both. A device that can only run numbers is a calculator, not a computer; you only get to call it a computer when it can do more things.