At Oxford you get the non-stupid-looking gown I think. Is there not a different gown?
Interestingly - a few of my friends are going to Oxford (Merton and Magdelen) and I'm no-doubt going to be invited to a formal or two of theirs. One has to wear ones current gown to the formal hall, and thus I'd have to wear Bristol's Undergrad gown. Fortunately Bristol uses the Oxford-pattern gown for undergrads (and a Cantab hood), so I can just borrow one of his mates' gowns.