on March 2, 2013
I used these in HD mode , they performed AMAZINGLY fast as hell. And BTW Art B, a card cannot shut down your HD mode, that was your camera firmware, your Cannon FW is the issue not the card. Of course Cannon is not going to admit that to you buddy.
I actually read the packaging specs before buying , I work as a photographer for a model agency and do freelance too in Los Angeles , and I must say that this WORKED REALLY WELL WITH MY NIKON ( BTW NICE PACKAGING , refreshing to see that) . A CLASS 10 is when both read/write are running at at least 10 mb/s or above . The write speed is faster than claimed 40 mb/s in HD mode , the read is 20 mb/s as advertised. So contrary to what Art B says, this is running beyond advertised (even in HD mode) , a CLASS 10 UHS-1 all the way through !
What impresses the hell out of me is that they are almost indestructible. Waterproof , Magnetic, and Temp resistant , I can't pay top dollar for that anymore via Sandisk, You can't buy a Sandisk with this type of ruggedness at this price, no way ! that is on their higher end pro series. Above all they are performing far better than my Sandisks , I might be converting over officially to this young brand from Monster Cable on the SDHC cards .
on September 25, 2012
Touted as high speed class 10, but diagnosed by Canon service as the culprit to my videos shutting down early in HD video recording mode, but not in standard def mode. Apparently class 10 read speed is guaranteed, but write speed is not guaranteed. So it is not even defective, it meets the standard but this card is actually slower than a Class 6 card in write speed. Or at least it is for this particular card. Disappointing, I thought I was getting a fast write speed.