Naming the best portable hard drive was a tough call for our editors. We found two models that both get excellent reviews from professionals and users: the Seagate Backup Plus Slim (Est. $75 for 1 TB) and the WD My Passport Ultra (Est. $85 for 1 TB). The WD drive has more recommendations overall: Both CNET and PC Advisor award it 4 stars out of 5, and it has high overall ratings from more than 1,500 owners at Amazon.com and more than 300 at BestBuy.com. The Seagate also gets 4 stars from CNET, but it's not covered in any other computer publications, and it hasn't received nearly as many reviews from owners -- though it earns comparable overall ratings.
However, in a head-to-head comparison at The Wirecutter, the Backup Plus Slim edges out the My Passport Ultra in every possible measure of quality. It's slimmer and lighter, and it narrowly outperforms the My Passport in nearly every test of speed. Moreover, the editors say that while both drives have fairly low failure rates as reported by Amazon.com users, the Seagate drive is slightly lower. While some new Amazon.com reviews have popped up since The Wirecutter posted its report, the overall ratings for this drive remain highly positive, and the complaints about the drive are more likely to focus on its software than on hardware failures. Thus, for reliability as well as performance and value, the Seagate Backup Plus Slim earns our Best Reviewed pick.
While the Seagate Backup Plus Slim offers a lot of benefits, there are two features it doesn't have: rugged construction and a super-fast Thunderbolt connector. To get both of those features in a portable drive, your best option is the LaCie Rugged USB 3.0 Thunderbolt (Est. $200 for 120 GB). This drive comes in two versions: a standard hard-disk drive (HDD) in sizes up to 2 TB, or an even faster solid-state drive (SSD) that maxes out at 500 GB. The SSDs are considerably pricier, ranging from $200 for 120 GB to a whopping $500 for 500 GB. However, even the HDD version is more than twice as pricey as the WD and Seagate drives of comparable size.
Is the LaCie's high price tag justified? That depends on your needs. It's undoubtedly one of the fastest portable drives on the market; in tests at CNET, the SSD version reached speeds of around 150 Mbps for both reading and writing. (The Seagate Backup Plus Slim, by comparison, gets about 120 Mbps, and the WD My Passport just slightly less.) It's also very sturdy, with an aluminum enclosure and a rubber orange bumper around the edges that the manufacturer says will protect it from falls of up to 4 feet. Reviewers also describe it as very easy to set up and use. In general, they recommend it as the best pick for users who need a portable drive with top speed and rugged construction. However, the Seagate Backup Plus Slim offers better value.
If you want a rugged drive but don't need the Thunderbolt connection, a much cheaper option is the Silicon Power Armor A80 (Est. $85 for 1 TB). According to The Wirecutter, this drive is even tougher than the LaCie: In addition to surviving a 4-foot drop, it can withstand being submerged in a meter of water for up to 30 minutes. It's not nearly as fast as the LaCie; in tests at CNET, its USB 3.0 connection reached speeds of only 87 Mbps for reading and 103 for writing. If you care more about safety than performance, however, this drive could be a decent bet.