i have been looking into the idea of getting an external backup hard drive for a while now and this is what i have discovered: - if you want one its way cheaper to buy the external drive case and buy the hard drive of your choice seperately, this will save you a lot of money and it will be a better fit for your needs. - most inexpensive external drives use usb interface which is slow as chit and takes forever - getting aa eSATA external drive is best but not all computers have ESATA plugs for it so plan on adding a pci slot or drive bay interface to older systems. - getting a usb to eSATA adapter is a waste of time so just get the usb drive if you need universal connectability and expect slow transfer speeds. - if you are using this as a backup drive to restore your computer in case of a virus, you are not supposed to keep it connected or update it frequently since doing so will corrupt it with the same virus that destroys your computers main files. - if buying an external drive the plug and power source are the most likely to fail due to overheating or poor quality so pay close attention to them as well as how convenient they are. (having plugs and converters all over the desk isnt very convenient especially if its staying plugged in all the time. ==================================================================== now i just wanted a fresh clean restore drive to fix my computer back to the way it was in case i got a virus. my solution was to simply add another internal drive to my computer, ghosting a fresh clean install to it, then leave it unplugged. if i get a virus i just reformat the infected drive to kill the virus then unplug it. now i just plug in the other drive with the ghosted image on it and im finished, windows is already installed, updated, and registered. all my programs and files are also installed and working too. all i have to do now is ghost an image onto my other drive which is now blank after having been formatted. after ghosting i unplug that drive so it is no longer in the system and it is a virgin backup that cannot be infected. this sollution only works best if both drives are of the same gb size (its hard to ghost to a smaller drive than the original) and it has to be used on the same computer or it doesnt work without needing to be reregistered. ===================================================================== these are my thoughts on external hard drives: prebuilt external drives are just not worth buying because its much cheaper to build your own. if you need your files updated regularly then use a thumb/flash drive for all your data files. now for regular updating of media files an external backup drive is a good choice to protect against losing your files because of a drive failure but it wont protect you from a virus.