Flash memory is a boon to digital multimedia capture. From digital camcorders to digital audio recorders and other high speed devices that use SD cards, flash-based memory lets you keep up with the pace of real life in high quality. SD cards, like other media, vary in their read and write speed, which is particularly important when capturing live audio or video. Speed is expressed in two ways: x-speed rating and Speed Class Ratings. The latter is the official standard recognized by the SD Association.

Why do high speed SD cards matter? For one, it can significantly cut down on your transfer time, which is helpful when backing up large batches of digital videos or digital pictures. But it’s also important to have a high speed SD card when shooting HD video and high fidelity audio, to ensure that there aren’t any glitches, errors, latency or gaps in recording.
The following high speed SD cards outperform in terms of speed. They cost a bit more, but for serious professionals, a high speed SD card is a must.

SanDisk 8GB Extreme III SDHC Memory Card w/Reader - $26+

The fastest SD cards are classified as Class 10, which means that they have a minimum write speed of over 10 Mbps. SanDisk’s Extreme III SDHC memory cards, however, purport to go above and beyond this standard by attaining write speeds of 30 Mbps. In other words, the only thing that holds back the SanDisk Extreme III is the speed of the device itself. Of course, for such high end speed and performance, you’ll pay a premium. On sale, the SanDisk 8GB Extreme III SDHC memory card can be had for $26 (flash card reader included). But regularly priced, it could set you back over $50.

Transcend SDHC Class 10 Card - $20.95

What do you get when you forgo the brand name clout of SanDisk and go for a Transcend SDHC Class 10 Card? For one, you’ll pay about half as much per GB. The card will also get you write speeds up to 20 Mbps, which is a wee bit slower than the SanDisk Extreme III, but still lightning fast and suitable for HD video recording. Plus, Transcend gives lifetime warranties for their cards, which is a perk, if only for your peace of mind.

Lexar 8GB Professional 133x SDHC Card - $25.00

The Lexar Professional line of SD cards are advertised with their x-speed rating, but officially, they are Class 10 SD cards with 20 Mbps. Don’t be fooled by the larger number with the x-speed rating—it’s the class rating that counts. Overall, these are excellent SD cards with plenty of speed and at a comparable price point to the SanDisk Extreme III cards. Lexar is recognized as a standard in professional memory cards, preferred by photographers for their speed and reliability.