Is the only difference between the two memory? How much space is already taken up by the OS and other stuff, i.e. how much free space does the 8GB really have? Also - can the a100 use the memory on the card "live" or is it only good to transfer stuff to the tablet's internal memory? I just scored a 32 gb class for micro SD card for a good price so wondering if I should save the 90 bucks or so and go with the 8 GB.. that is if I dont go with the Samsung Plus I have also been looking at, but that is 150 more than the 8 gig.