Most reports that I have read state that the Defiant was a dreadful aircraft and only showed early promise whilst the Luftwaffe pilots confused it with the Hurricane and got a 4 gun shock whilst attacking from the rear.
Below is the Gloster entry for the same competition that the Hurricane won. It is a shame that it wasn't picked up at the same time as the Hurri. One thing that I would like to know is.....Did one of the Gloster engineers have a Japanese uncle who worked at Mitsubishi?