A family member of mine had a Transcend StoreJet. It was a ruggerized external drive, with a thick rubber coating around the drive. It was too bulky, heavier and not really portable. Performance was satisfactory, though.
It depends what kind of external Hard drive you are looking for. If you want to carry it around in your pockets, then buy a slimmer drive (not many options here; i.e. a Slimmer drive also having "Safety" features. If you are OK with bulkier drive, then you can find many options.
It'd be wise to create a thread in respective section, post in detail whatever you require and get a better opinion from masses.