personally, nay other component can be replaced easily, taking pretty much only aslong as it takes to deliver. If a HDD goes down otoh, you will lose any data, files etc since your last backup - even then a reformat & os reinstall can take a long time, especially if your a Type A personality fiddling and tweaking eveything how you like it. Not something to skimp on IMHO. I think that since these individual drives have already been rejected by someone, chances of it being a duff drive must surely be greater - its not exactly common for hdd's to be incompatible with someone's soundcard or something.