SDXC cards carry on from where the SDHC format leaves off, with increased capacities and faster performance. The Integral UltimaPro is one of the latest in the developing range, with its 64GB capacity ample for hours of video or thousands of high-resolution images.
Its Class 10 designation guarantees a minimum 10MB sustained write speed per second, making it ideal for continuous high-definition video recording. When used with devices supporting the UHS-1 interface, write and read speeds are said to be as high as 60MB/s and 35MB/s respectively.
Sadly, most current cameras don't support the UHS-1, and Integral quotes maximum transfer speeds of 23MB/s where this is the case.
The question then arises as to what benefit users of current or older cameras stand to realise from the memory card. To test this, we pit the card against a Class 10 SDHC card with a maximum write speed of around 20MB/s.
When writing images in-camera, the Integral card showed a speed advantage of around 30%. When used with the supplied card reader to transfer the same amount of information to a laptop, the Integral card again displayed a better performance, but here was only around 20% faster.
These results should make it clear that while the newer technology does have an advantage, it's not significant enough against its price for those who don't yet own UHS-1-compliant products.