Been in Tesco this afternoon and find this. It is a 3.5" don't know what hard drive is inside.
The Tesco Direct as well,http://direct.tesco.com/q/R.204-3017.aspx
first post from me. I ordered a Hitachi 1TB from Ebuyer for 64.99 free delivery and do think this one is another option if anybody wants some mobility.