Memory companies large and small are renewing efforts to popularize USB sticks with expandable microSD slots.

Such products are one way to move data between mobile devices, which often have microSD slots, and desktop or laptop computers, which usually have USB slots. Also, sticks can be more convenient than standard card readers because no cable is involved.

SEE: Portable storage policy (Tech Pro Research)

Kingston Technology on Monday will announce its Duo3C, which is a card reader in a pen drive form factor. Duo3C will have a suggested retail price of $20, it will be available initially in foreign markets, and it is expected in the US by the end of this year, Kingston flash card business manager Annette Chan said.

The idea for Kingston is not its first rodeo. The company in 2008 debuted a similar product called DataTraveler Micro Reader. But it was twice the price of standalone USB sticks and got discontinued in 2009, explained Jean Wong, flash USB business manager, who was part of the Micro Reader team.

Smaller companies such as Link Depot and Tera Grand currently sell similar products. Link Depot has its uninspiringly named U2-PEN-HD-SD-MMC-RDR. Tera Grand aimed higher at least in branding with the UltiFlash. Kingston, of course, has far more reach.

A multiple-slot concept emerged in 2011 from online magazine Yanko Design. Crowdfunded startup Vast Corp. is working on the same idea now.

“The objective of doing this is not just to provide a commercial product but also to provide eventually an enterprise product,” founder James Cerrelli said. Vast announced its plan for a multi-slot VastStick last year to little fanfare. Since then, the company renewed its crowdfunding effort and was met with Reddit controversy. Meanwhile, engineers developed a method for combining the cards into RAID configurations, worked on reducing power draw, and made the device smaller, Cerrelli said.

VastStick should be for sale by the end of this year, Cerrelli said. A docking station is also being designed for transferring data to clouds, he added. VastStick will probably cost $180-$200, cards not included, he said.

SEE: CompTIA IT Security, Network & Hardware Certification Training (TechRepublic Academy)

What to consider before buying

Computer memory consultant Brian Berg, who is technical chair of next month’s Flash Memory Summit, said such products can work well if the designers use high-quality components and an architecture sophisticated enough to handle the throughput. Too often there are cheap components and shared controller chips–that puts the product at the mercy of its software.

“You’re susceptible to funky firmware,” Berg said. “I would be suspect of these devices in this really small form factor having any real credibility. If you put four microSD cards into it, you’ve got five things at play there. You’ve got the cards and the device itself. That frankly makes me nervous.”

Another factor for buyers to consider is whether published performance numbers are in bursts or consistent throughput levels, Berg added. Generally, he said, “Spend the money to buy good quality, and you can expect the best out of that.”