I have the Tilt Box (not sure if 1 or 2), which seemed to be the starting point for all the others. Gift from a friend, hardly ever use it. Powered it back up a few weeks ago after several years in storage, with the battery out, still worked fine.
My biggest beef is it's so dang big. For KISS stuff, it's ok, but I'm often trying to measure some small internal angle where that thing won't come close to fitting in any direction. But none are digital.
So I buy every protractor type tool I find, and they come out much more often than the tilt box.