Useful consumer review: The SanDisk Ultra Flair 64GB USB flash drive I bought last summer survived less than 1 year of rattling around in my bag.
Basically it has been on a keyring with a Yubikey Neo the whole time, and it just stopped working. As in nothing shows up in syslog or dmesg, and the USB device gets very hot quickly when inserted into a USB-port.
I tried prying it apart, to see if something was shorting and that was why it didn't work, but even inserting just the "core" of the device, without the casing yields nothing registered by the computer and a very hot device.
While it worked, it worked fine - but less than a year until catastrophical failure, without any warning, I give it 1 star.