Do not buy!
From a newsletter: Mental Case will remain available for a while in the Mac App Store." Happens now the second time to me, that they make you buy a new software (they call it here "Studies 1.0", the last time they called it "Mental Case 2.0"). Also this time, the software wont get better, sync was hell.
gluino about
Mental Case — Flashcards for the Serious Student, v1.7.1