There's another outfitter for Cambridge college gowns and theirs is more expensive (but better quality) than R & A's. But almost all students I know got theirs from R & A (or their college sold theirs at the beginning of the fresher's week).
It's all black, and they're mostly drunk when they're wearing it at formals
, so nobody cares (or notice) about the quality of gowns others wear.
But JCR usually sell second-hand gowns they got from graduates at much cheaper price, so that's another option.