Well I'm getting 2x Spintpoint F3's tomorrow and gunna stick them in raid 0. But anyway I was wandering looking at a couple of threads on different forums I saw someone got his read and write to 296 MB/s in raid 0 and thats quite close to some SSDs but the only difference I saw was that the 4k and 512k (Dunno what they are saw them in the test) are much slower, anyway my question is what are the 4k and 512k actually used for as I have no idea ;'P