Flash memory devices like USB keys have plummeted in price, and they're a simple, portable means of saving and transferring data. But would you want to rely on them in the long term?

Pros of backing up to flash memory

Unlike hard drives, flash memory storage – as used in USB sticks and memory cards – has no moving parts, which means it’s much less prone to mechanical failure. 

Flash drives and SD cards are, of course, extremely portable. Though of course, this can make them easier to lose.

Cons of backing up to flash memory

The downside of flash drives and SD cards being portable is that it can be easy to lose an entire drive full of valuable data down the back of a sofa, in the washing machine or, even worse, somewhere public, where strangers could potentially gain access to your private data.

Data can still become corrupted during transfer, however, or if a device is detached from a PC without using the Safely Remove Hardware tool in the Notification Area.

The other major drawback is cost. Although prices continue to fall, flash devices are still relatively expensive. You can pay around £14 for a 32GB flash card. The maximum flash capacity you're likely to find at present is around 250GB, and you can expect to pay through the nose for this much storage space.

Verdict:

Flash memory is quick and convenient, but it doesn’t work out cheap and is vulnerable to loss. It isn’t suited for large backups, but it’s useful for making portable copies of files.