Beware, Solid State Disks based on Flash memory (which most if not all are) have a limitation on the number of writes that can be performed which means that over time as you continue to write to the device you will eventually reach the limit of your device and won't be able to write to it any more. There are two types of flash memory, MLC which is cheaper, more dense and lower number of write cycles and SLC which is more expensive but has a higher write limit. This is most likely why the drives have a one or three year warranty. The warranty may also not apply if you have performed "excessive" writes to the device.
Most SSD flash drives are engineered to distribute the writes across all of the flash memory in the device to ensure that one section doesn't "wear out" prematurely. They also have more capacity than the user is able to use to also extend the usable life of the drive.
I hope that this helps. The MTBF number you are looking at is so high because SSD drives have no moving parts which inherently makes them more reliable. That being said, all electronic equipment can be damaged due to power issues, ESD, internal circuit flaws, excessive heat, etc.
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