Ranked in these QuestionsQuestion Ranking
Pro Very portable
At 0.54lbs, it's quite portable and easy to just throw into a bag and carry around.
Pro Relatively long warranty
The WD My Passport comes with a 3-year warranty.
Pro Large Capacity options
Models available to up to 4TB.
Pro Supports Mac and PC
Supports both NTFS and HFS+(needs formating).
Pro Has a backup software
Western Digital provides a backup application that can be downloaded from the manufacturer's site. You can use the application to create automated backups or manual on-demand backups.
Pro WD is generally more reliable than Seagate Drives
Con Relatively slow for single-file transfers
Even though it has a 201.8MB/s write speed, according to benchmarks it's surprisingly slow with single-file transfers compared to other portable hard drives.
Con Doesn't have a Thunderbolt port
If you use a Mac or a higher end Windows unit, you may have experienced the speed of Thunderbolt external devices. Thunderbolt drives are more expensive than USB drives. Though, a similar 5400 rpm drive using a Thunderbolt connection can read 1.5x faster than USB 3. But you may not care depending on your usage. It has not hurt some users, some 80% of computer users will not find any benefit to Thunderbolt.