Is the U Disk Fabulous or a Scam?


When is a flash drive a U disk? Never; I don’t think hybrids exist. But they’re being sold as if they’re flash drives. And U disks are awful.

Users likely are confused when they think they have flash drives and don’t know the difference. They look alike. There’s no difference on the outside, other than maybe text. The price is cheap.

(This is unrelated, I think, to udisks2 and, I guess, a predecessor which might be called udisks, which is software. This is about the lousy hardware called U disks.)

I wanted to buy a flash drive with an LED. They’re getting scarce, so I searched more extensively. I’m geeky and careful, yet the retailer’s description slipped right by me. The U disks came up as flash drives. I thought they were flash drives. Then, a seller emailed me that they sold me a U disk. I decided I’d better look this up.

What’s inside a U disk is another story. It’s not solid state. It has a tiny magnetic hard drive. So, it has at least one platter that spins. The interface is USB.

The platter has to be tiny and yet has a capacity measured in multiple gigabytes. That has to be amazing. If it has two platters, or more, that’s even more amazing. I didn’t know it was possible (for less than, say, thousands of dollars) to make a motor, a platter, and a moving read-write arm and head with that much storage capacity and put them into one air-tight container that’s half the size of a finger. To make a profit selling one for ten dollars, you’d have to make a lot of them. Like most technologies, they should work reasonably well or they wouldn’t sell. Since they haven’t disappeared from the market in all this time, perhaps they’re good. But, no, they’re miserable.

If you want to read about them, good luck. There seems to be very little online literature about them, especially odd since they’ve been sold for about nine years and counting. There should be a large body of user experience with them by now, because retailers can’t have sold only a few without charging premium prices and still be offering them years later, so there should be online reviews. Hardly any have appeared, even fewer by anyone who knows the difference. Someone should do a comparative test against a solid-state flash device sold in the same year and with similar capacity. I haven’t seen a test like that.

When I shopped, several models were available. I bought one plus a spare, with different brandings (maybe none), so I’d spread my risk. The pricing was about the same as for a flash drive. I thought I was getting flash drives. My mistake.

They’re less reliable than flash drives (and that’s just judging from the lit, and my experience confirmed it), you should keep them far from magnets and magnetic fields (for example, don’t keep them near power supplies or thick power cables unless there’s no electricity going through them), and they’re not under any major brands. When I tried reformatting one, I had problems that took me hours to sort out. When I saved gibibytes of file copies, its behavior spooked me, although I’ve since forgotten what exactly it did. It is much slower than a flash drive, so beware of saving a large load of files at a time, as that couold take an hour or more. One came with software that the seller denied supplying; after a few emails, the seller acknowledged the software’s existence and said I could delete it; I guess the software was an artifact of their having formatted the drive.

They’re probably also less trustworthy than the hard drives that come inside your computer. HDDs are maybe a dozen times bigger, which makes manufacturing easier, and the higher prices on large HDDs give more capital for building each one. That means HDDs should be more reliable than a U disk made in the same year. U disks probably cost less than flash drives to make and are as convenient as thumb drives in general, but we don’t have to settle for what’s unreliable.

Possibly, these are meant for bulk sale as corporate premiums, things businesses give away free with their logos. If they’re free, you don’t expect them to be good. You shouldn’t put important files on them.

Don’t get a U disk.