I've only had one on a low-power PC used as a router in a relative's house. I had set a spin-down timer, and the spin-downs/ups probably killed it.
I haven't yet had a crashed drive at home, but I do keep them cool which I suspect helps. I also don't use my critical ones for longer than 3 years (for which they're on 24x7).
BIOS-based RAID varies from one extreme to the other.
The better ones will present the mirror as a single logical drive (or LUN) to the operating system, which won't know there are two or more disks behind it. There may be some management tools available in the OS which enable you to see the real disk layout. The RAID BIOS will have a configuration utility you can access by booting the system and hitting some key sequence to enter it before the OS boots.
At the lower end, the BIOS is simply aware of the RAID so it can boot from it (read-only support), but the disks are still presented separately to the OS and a kernel driver in the OS takes over the RAID support as soon as the BIOS has loaded the OS kernel and boot device drivers.
You can also do RAID in software for most OS's. That's pretty much the same as the case above, except the BIOS doesn't know and if the drive which it is configured to boot from dies, the BIOS might not automatically boot from a mirror without you reconfiguring it to do so.
For the BIOS-aware RAID, you usually cannot invoke it without destroying what's currently on the disk - it needs to be invoked before the OS is installed. Some OS-based RAID can be activated (e.g. turning a single drive into mirrors) without losing the original drive contents, but this is not possible in all cases.
My experience is all with Enterprise grade ones. They eventually wear out, but that failure happens when you write to them, unlike spinning rust disks where you normally only find out when you fail to read from them. A worn out [Enterprise] SSD simply becomes read- only so you still have all your data, whereas a worn-out spinning rust disk becomes a door stop. The wear out of an SSD is completely predictable, whereas that of a hard disk is much more random, although you might get a brief SMART warning if you're lucky. Of course there are other failure modes too (such as controller failure) which can be equally catastrophic for both types.
If you mirror identical SSDs, you _must_ keep an eye on the wear levels, because they will both wear out at exactly the same rate. I've seen several cases where people have not realised this, and lost both sides of a mirror within days, after 2 or 3 years heavy use in an Enterprise environment. (I'm not sure a home user is ever likely to wear out an SSD in terms of running out of write cycles, but I'm not sure how consumer grade SSDs compare for available write cycles.)
USB thumb drives tend to be very much lower quality, and there are many fakes around which have had their capacity upped by including non-working parts of the flash memory.