I've gotten four of these for both of my Nikon D7000's and have had little bit of an issue with the adapter cards being out of spec and sticking in the Nikon Camera SD Slots, and one of my card readers. Sure enough, i sanded one down carefully and it fit perfectly.Performance wise, these things scream over regular Class 10 or Class 6 cards and perform nearly excellent. I cant complain other than I wish they were faster, but I'm not getting that for a while at $23 per card.