I must be doing something wrong, I've never had a dead HDD.
My ex had a Maxtor in her PC, which had problems with bad sectors etc and was then put in my Amiga where it's worked okay since. I've had to be careful how I partition it though... Not surpisingly I take regular backups!
My original HDD was a Western Digital Caviar with 420mb, later replaced with a Samsung with 4.3gb. This was supplemented with the dodgy Maxtor soon after, giving a total of 15mb which was (is) a vast amount of storage space for an Amiga without broadband.
My storage hungry PC has just been gifted an additional 80gb which is already 20% full after a LAN session last weekend, but there's lots of room for my WinUAE stuff.