I stand to be corrected on this but I think it is 13.8TB That is big. But again costly. I was told however that N-as will be solid-state soon and then it will be stable to the point where they just will not give in that easily. Yet it has been my personal experience that you don’t want to much stuff one a single storage device. See if a 13Tb backup goes then it is 13Tb of corrupted data. I can imagine bigger companies investing in both N-as and perhaps tape backup systems “they are big” but for the smaller company a little N-as with Blue-Ray or standard DVD might be just as effective. However everything has the hidden potential to get corrupted so don’t just look at backup also make sure that you do backup everything once a day. The more backups there are the less change there will be for total data loss.