JMB 320 simple really, to meet the application requirements SATA to 2 * SATA functionally. JM 20330 quite a history of product but its SATA ← → IDE application was focused, and will continue long been needed. JMB 321 enables SATA to 5 * SATA expansion / HUB choice. JM 20329 JMicron products USB to SATA originator, the reason for enduring, because it is practical, stable performance and a relatively affordable price. JM 20337 a master, three kinds of interface USB2.0 to IDE + SATA. Is not function very comprehensive and powerful. JMB 351 USB 2.0 to 2 * SATA raid function is usually used as realized. JMB 352u features not generally powerful USB 2.0 to 3 * SATA or USB2.0 + Esata to 2 * SATA and cloning capabilities can be realized as [a master disk, two disks were cloned as a child].