Have 2 2013 MBA 11 i5/4/256gb in hand. Both have Lg screens, but one has Sandisk SSD and the other Samsung. Which one would you keep? The samsung seems to have a higher write speed, but if it's anything like the 840 Pro, the fuller the drive is, it becomes much slower. The Sandisk has a lower write speed, but seems to be more immune to being full. Which one to keep?