I recommend SD cards from Sandisk or Samsung. I've never had any of those go bad. When you get an SD card, i also suggest that you buy from a reputable store like Best Buy or Amazon (actual Amazon, not 3rd party seller). There are many counterfeit SD cards sold by 3rd party sellers on Amazon and also many counterfeit SD cards sold on eBay. If the price looks too good to be true it probably is.