Re: SSDs and HDDs both require backup...
That's exactly one thing on an HDD that can give you a warning, the noise.
I've shut down and mirrored two HDD's because of 'oddness', that you can hear (cclicking, rpm winding up and down when it shouldn't really), and, wouldn't you know.. a few weeks later, a loud scrrrrech, and a sudden BSOD later, the HDD refused to spin up after a reboot.
One tip, if you DO hear that sort of noise, DON'T DO A WINDOWS DISKCHECK.. all that will do is bounce your heads all over the good bits of the platter; Take the disk out, put it in as a slave on another machine, and just mirror it to another HDD.. then you can do your fault check.. which will probably destroy everything anyany.
Luckily, these (it happened twice over 10 years), were home PC's, with nothing but banal crap, re-installable games, personal e-mails containing nothing that I couldn't recover from the imap, and personal docs and pics that were always backed up..
So, in a sense, HDD's can and do give more warning of a problem, but you can't rely on it, and you have to be physicaly present to hear said telltales.. HD drives, in their death throes, failing in a server room, with no one present, would need to be striped across multiple discs to prevent data loss.. oh wait.. that's exactly what happens..
SSD will never replace HDD RAIDS for secure ('secure' in this case meaning nonvolatile) storage.
And if you're at home, infront of your PC, you WILL have a better chance of physicaly hearing a problem before it becomes terminal / expensive.
But still, back yo' shit up. Ain't nobody needs that sort of data loss round these here parts..