absolutely no difference between an internal or external harddrive really.

an external harddrive is basically a hard drive (like in the links above) encased in a box to keep it dust free etc. with maybe a few extra toys such as cooling, flashy lights, remote control etc etc.

just looked at that one, your paying a lot for nothing really unless you will actually use the features?

if your pc crashes you wont lose a thing mate, you'll only lose data if your half way thru writing (and it crashes - therefore you might lose whatever you were saving/copying....unlikely as hell!) or the hdd corrupts (which is again HIGHLY unlikely lol - and remember internal/external are ultimately the same inside so both can fail the same)