CNET’s expert staff reviews and rates dozens of new products and services each month, building on more than a quarter century of expertise. Before anything else, you'll want to figure out how much you're willing to spend on a new external drive and whether you can afford a Solid State Drive in the capacity you want. External drives start at 500GB and go all the way up to 22TB or so. For a lot of people, especially if you're looking at a faster SSD, the storage sweet spot...