Particularly with the advent of USB, external hard disks have become widely available and inexpensive. External hard disk drives currently cost less per gigabyte than flash drives and are available in larger capacities. Some hard drives support alternative and faster interfaces than USB 2.0 (e.g., Thunderbolt, FireWire and eSATA). For consecutive sector writes and reads (for example, from an unfragmented file), most hard drives can provide a much higher sustained data rate than current NAND flash memory, though mechanical latencies seriously impact hard drive performance.
USB flash drives usually specify their read and write speeds in megabytes per second (MB/s); read speed is usually faster. These speeds are for optimal conditions; real-world speeds are usually slower. In particular, circumstances that often lead to speeds much lower than advertised are transfer (particularly writing) of many small files rather than a few very large ones, and mixed reading and writing to the same device.
The SanDisk PRO gives you blistering speeds, offering 420 MB/s on the reading front and 380 MB/s on the writing end, which is 3–4x faster than what a standard USB 3.0 drive will offer. The sleek, aluminum casing is both super durable and very eye-catching, so you can bring it with you to your business meetings and look professional as well. The onboard AES, 128-bit file encryption gives you top-of-the-line security for your sensitive files. That USB 3.0 connection is also backward compatible with USB 2.0, so you won’t hit any snags with an older computer. SanDisk is so confident in the functionality of this little drive, that they’ve even backed it with a full lifetime warranty in case any issues befall it. Finally, there’s a file backup system you can download called RescuePRO that will let you recover lost files if needed.
There's a lot to choose from when it comes to buying a flash drive. The most important thing to consider is size. The whole point of a USB drive is to store lots of data in a small space, so think about what kinds of files you'll want to house on your flash drive. Movies and music take quite a bit of space, so if you're carrying your whole entertainment library with you, you'll want a big thumb drive – at least 16GB. Books and other text-based documents require relatively little storage space, so people like students and working professionals using Microsoft Office would be happy transferring Word documents or Excel files with as little as 1GB of space. On the other hand, if you are using photo or music editing software, you'll want a USB flash drive with lots of storage capacity to transfer graphic and music files.