2TB USB hard drive for backing up

[Sian Mountbatten <poenikatu@fastmail.co.uk>]

I am going to buy a big USB hard drive to backup films, music and 
photos. In fact, I might backup the system (at least, the list of 
packages installed).

Anybody out there tried a 2TB USB hard drive? What did you use as filing 
system. I am intending to use ext4. Any comments?
--
Sian Mountbatten
ex-Algol 68 specialist