Yes, but I would like to know what to look for, can at least hypothesize since I have the same drives some will most likely develop the same issues before "walking out" on me. :D

Unfortunately I had a Western Digital drive do that exact thing to me, minus the SMART warnings.

Speedfan to check S.M.A.R.T status; unfortunately there is not much of a warning at times. In three occasions, the drives were working fine the day before, on the following day during boot up a BIOS message prompts "your HDD is leaving you, back up the disk". (not the exact words mind you :)".

At one time, the BIOS won't recognize the HDD at all. When she decides to leave you she doesn't give you the normal two weeks notice. Sometimes she will "b***h" for awhile, a signal that she has had enough of you. 1 WD, 2 IBM (hitachi now) and 1 Seagate, surprisingly I have 4 or 5 4.3 GB still in good condition after +5 years of use.

As long as she doesn't win the inevitable custody battle over all my stuff, I'll be happy. ;-)

Hence, backup "plan". ;) including hiding some of your assets such as offshore banks and property investment etc.

if you get bad sectors and really want the data back, you can try the freezer trick

today one seagate comes to me, it is better than WD or hitachi whose I had in my computer, it is very quiet and it's faster than other HDD, but if you buying new seagate took at last number who needs to be on 250gb
310AS (disc with 8mb cache)
4100AS (disc with 16mb cache)
On 320gb and 400gb:
620AS
and on 750gb 640AS