I apologize in advance if this question has been addressed somewhere else in the forum and also that it is slightly off topic, but I have just now gotten to the point of needing to put books on a memory card (specifically an SD card) as my internal memory is full, and I am wondering if you can leave it in the slot all the time or if you should store it in it's case when not reading from it. I am geting the new M-Edge case and the pictures show places to store the cards in the cover. Just wondering if there are any recommendations regarding this.