Which pocket hard drive you choose depends on what you need it for. Do you need backup software? If the Windows’ backup system works for you, then the ArcDisk is a very cost-conscious solution. Is security an issue? The 128-bit encryption provided by Imation could be the answer to that need even though the price of the Imation drive is a bit higher than its competitors on a relative capacity basis.
What type of files will you be transferring? Drives with larger buffers (such as the Seagate and Sony devices) appear to do better with small numbers of large files and badly with large numbers of small files. You’ll age gracefully while waiting for them to complete a system backup, but they’re at the top of the class for video or music file transfers. Price is the separator for those two, with Seagate getting the nod for now.
Do you want a boot drive, perhaps to run an alternate operating system? You can probably massage any of these into that task (if your PC’s BIOS allows it), but Seagate gives you the software to make its drive bootable. Nothing could be simpler.
As for design ignore it. Despite their size and looks, these really are hard drives –not artwork. You’ll do fine if you select one for your needs, not just because of how cute it might look.