I've had this for about a week now and so far no problems. Due to my laziness, I didn't do a lot of research beforehand and didn't find out about the problem these cards had with the Galaxy S4, which is the phone I have, until after I had bought the card (apparently the cards kept unmounting themselves, even if you remounted it in the settings). Fortunately, SanDisk caught wind of the problem a couple months ago and fixed it, so kudos to them.