I am writing this review while about 6 month passed from the delivery. It was working great like a high speed class 10 memory, and after just three month, it was suddenly broken and it is now faulty for no reason. I tried to contact seller and he was not happy with an exchange since more than 1 month passed from the bought day. He recommended to contact the international retailer in Taiwan. I really tried to catch them for several times within last three months by phone/email, but I could not managed to find any responsible party for an exchange/refund because of its lifetime warranty. I will strongly recommend not to buy the Kingmax memory since that is just the waste of your money in case of failure in your device.