I can attest to running desktop drives 24/7 for years. Even my 2.5 inch blue has about 3 years, but since it spins down most of the time, it has a pretty easy life. Has a 3.5 inch blue before that, but wanted the lower power(and quieter it it was not for the parking) of the 2.5inch one.
I was simply referring to design specs. Everyone who overclocks knows you can go pretty far out of spec and still work without issues for years.
If your database is heavy random read/write(most would be) a SSD of suitable size will kill even the best hard drives(raid0 or not because Raid0 does not help random). If redundancy is the concern go with raid1. It is not faster(maybe even a bit slower), but a drive failure will not leave yours database...