To: AC

capacity, speed and price is what the average (inexperienced) consumer might be looking for, but if you have had more than a few drives with valuable data die, you will value reliability more than anything.

I personally value absence of noise and (lack of) heat more than speed too, at least for drives that will be located anywhere near me (I obviously don't care about noise for datacentre drives).

That's why I just bought 4x 1TB WD-GP (5400rpm) drives to use in a raid5 array, instead of 7200rpm alternatives.

And before you mention backups or RAID, even if all the data is backed up, failed drives are always a risk and certainly a hassle, remember murphy's law.