Theoretically they all should be the same as there's only one e-ink panel manufacturer atm. The bezel on each of the devices however may be of different lengths. So if you have access to multiple ebook readers (sony, kindle, etc), you should probably measure them and find the best fit.
I've also emailed both wrapsol and invisibleshield about this, but they have not bothered to replied, so it seems unlikely we will get a proper fitted one.
