did any of them happen to be sandisks, directly from sandisk website? I have NEVER HAD ANY PROBLEMS WITH sandisk, IT MUST BE authentic though. Used a micro sd card for the past 3 years, still works.
depending on what you use your micro sd for it depends on what class you should get, a higher class is not always better for your purpose. A higher class has better sequantial read write, while a lower class has a better read write. If you transfering files all the time, I'll stick to class 2 or max 4. If you're trying to shoot movies more of the time get a higher class. there's been a topic on classes of microSD, honestly you don't need anything more than a class 2, it has plenty more write speed than is used by our phone to shoot HD video.
ALSO lower classes are WAAAAAAAAAAAAAY less prone to get corrupt. keep that in mind next time.
HTC Amaze white: rooted S-OFF CM nightly | 4EXT recovery |
Samsung Galaxy Tab 10.1 white: Stock rooted honeycomb 3.1 | 18.104.22.168 CWM
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