Corso - Most either love or hate him...personally I think hes cool

Bowdarr- A Wookie as a companion...whats not to love? Besides the fact that gearing him up can be a pain pre50...(wasting planet comms on him for gear is dumb...and the GTN usually has stuff that is too expensive if the smuggler is your only toon)

Risha - Has an excellent VA and an interesting personality and a great dps toon as well.

Akaavi - Another interesting companion though I did not find much use for her ever battle wise.

Guss - A very hilarious companion. Made me laugh on more then one occasion