Mt Spokane Photography said:
Get one and test it out on your Canon cameras.
No, I'm being unfair. Canon has yet to make a camera that supports this card. They were announced in 2013 and the first cards came out in 2014, and a few cameras now support them, but otherwise, its a waste of money. I wonder how many buy them and then brag about their super fast card speeds. Of course, once the card has been used, then the write speed reverts to something like 40 MB/sec until a low level format is done.
The cards have a xtra row of contacts, and unless your camera has the extra row, your speed will slow way down. You will need a new card reader as well.
https://www.pretzellogix.net/2014/10/24/a-list-of-all-uhs-ii-sd-cards-readers-and-cameras/
Just to be clear, the 7D2 does NOT have the extra row of pins and does NOT support the ultra high speed... If you use it in your 7D2 it will be SLOWER than a 633X Sandisk card (about half the speed)... use one of those cards on a device that does have the second row of pins and it will default to 333X
If you want to see what works in a 7D2, check out:
http://www.cameramemoryspeed.com/canon-7d-mark-ii/fastest-sd-cf-card-comparison/
What this is, is an indication of future capabilities and I would expect future Canons to support UHS-II.
<EDIT> the Olympus E-M10 Mark2 supports it....