Well you can compare them easily in our wiki check
Boox M96 and compare the
Boox Max. They are very different machines. The Boox Max is newer and likely a bit better and has the larger screen. The Carta variation has a distinctly better screen but then you already have one that size so the N96 is your basic 9.6" device. Note that the M96 and N96 are very similar but the M96 page describes the differences.
Dale