The Reasons:
- After inserting the memory card tough behavior of Android 4.x
- Memory card is not always recognized by the computer / from mobile / tablet from
- Totaler data loss after a week use
It may be that I just had bad luck, but problems with three devices of different species make me skeptical.
Now I'm on a 32GB card swirled Class 6 from the house of Samsung. Here everything runs like clockwork.