There is a USB 2.0 similar style adapter available, but those flash drives are much slower than USB 3.0 of course... although they might do in a pinch and you are not in a hurry!
http://www.anandtech.com/show/4523/usb- ... ve-roundupLike USB 2.0 before it, USB 3.0 offers dramatically improved data transfer rates compared to its predecessor. Though specifications were announced in late 2008, consumer devices didn’t start ‘hitting the street’ until the beginning of 2010. USB 3.0 specifies transfer rates up to 5Gbit/s, compared to USB 2.0’s 480Mbits/s. USB 3.0 devices are downward compatible with USB 2.0 ports. Because of the ubiquity of USB 2.0 ports and relative rarity of USB 3.0 ports, this is an important consideration. Unfortunately, plugging a USB 3.0 device into a USB 2.0 port yields USB 2.0 transfer rates. Fortunately, computers with USB 3.0 ports are becoming increasingly common. Many newer laptops have at least one such port. USB 3.0 port expansion cards are available to upgrade older systems, and many newer motherboards feature two or more USB 3.0 jacks. Cases with front USB 3.0 ports are still rare, as are motherboards with USB 3.0 front port headers, but these will only become more common as time passes.
Anand reviewed an array of USB 2.0 flash drives back in 2005. He found that performance between different manufacturers and different models was quite variable. Because manufacturers often do not provide hard data regarding their drives’ performance, or sometimes provide ‘idealized’ transfer rates that don’t equal real-world capabilities, choosing between flash drives is problematic. We compare here a number of USB 2.0 and 3.0 drives in multiple ways, including synthetic performance tests and real-world use scenarios.
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Concluding remarks
We had three primary questions in mind when testing these USB 3.0 and USB 2.0 drives. First, how much faster are the USB 3.0 drives than USB 2.0 drives when each is plugged into their respective native port? The benchmarks and real-world scenarios clearly illustrate that USB 3.0 is faster across the board, sometimes by nearly 900%. Second, are USB 3.0 drives faster than USB 2.0 drives when both are plugged into a USB 2.0 port? Though USB 3.0 support is increasingly common on computer systems, USB 2.0 will remain more common and often the only choice for years to come. Our testing indicates that using a USB 3.0 flash drive in a USB 2.0 port yields better results than sticking with a USB 2.0 flash drive. Third, are USB 2.0 flash drives faster when plugged into USB 3.0 ports compared to USB 2.0 ports? Yes, but not by much at all—you'd likely not even notice the difference.
Are USB 3.0 flash drives worth the increased cost compared to USB 2.0 flash drives? We’ve provided performance data, and pricing is always variable depending on sales, rebates, clearances, etc. You might also want to consider how often you lose flash drives! (And how impatient you become watching transfers progress!) Given my personal USB flash drive usage patterns (occasional backups and data transfers), I think the Mushkin Ventura Pro, Kingston DT Ultimate, and Patriot Supersonic USB 3.0 flash drives are particularly appealing. These three strike a good balance between price and performance given today's prices. If you tend to write files rarely and read them frequently, the least expensive USB 3.0 flash drives provide substantially faster reads than USB 2.0 flash drives. However, if you use flash drives more often, such as frequently throughout the day, you’ll want to consider springing for high-performance models like the Patriot Supersonic Magnum and Super Talent RC8.
Finally, we’d like to thank the manufacturers for supplying flash drives for this roundup. We appreciate the samples sent from Patriot, Kingston, AData, Super Talent and Mushkin!