Very cheap per TB. Got on deal of the day for a steal. Works great to this day though I just use it to store my collection of items around 4TB in a redundancy of three 4TB drives. Writes fast. USB3.1 no complaints. got an excellent case with it that stores all my Micro SD cards so there is another TB right there in about 6 unused micro SD cards so it's kind of a all in one storage solution. No external power needed. No bank needed. Just plug the USBext plug into the drive and the other end into a USB 2.0 or above port and you just added 4TB (or 2 depending on purchase) to your computer or device using OTG (though impractical). Would buy again at previous price. Still a good deal just under $200.