Plextor are very good as well. Take into consideration the m3, m3pro, m5pro which will soon be available. They all have toggle nand which is the best and the marvell controller which, as far as I know, is the most reliable, a must for SSDs. Usually, the 256gb ones have better read/writes than 64/128/512gb, but not by a significant margin or at least one you can see except for in benchmarks. Samsung, Marvell, Corsair performance pro are good as well.