UHS-I SD cards should be about as fast. SanDisk has a 95MB/s UHS-I SDHC cards.
You do know that the 5D MK III does not support the UHS protocol?
Actually, I didn't. I have good CF cards, and it would take me a while to buy a 5Dmk3 (assuming I'd buy one), so I didn't check for specific SD features support.
If you have a UHS card reader you are ok, but the article is about USB 2 in the camera body.
Didn't plan for either UHS card reader or UHS cards.