To be fair to the idea, the Brits were putting turrets on almost every new aircraft spec in the mid to late 30s... Nonetheless, what did they know?
As for the Venom, Jeffrey Quill has much to say about it in his excellent book Spitfire A Test Pilot's Story (John Murray, 1983):
"The Venom was a sporting little aeroplane. it could not match up to the Spitfire's performance but it was doing around 325 mph at about 15,000ft. it was extremely manoeuvrable and delightful as an aerobatic aeroplane. Its big trailing edge flaps which came down to 90 deg produced a great deal of drag which killed any float during the flare-out for landing. One could put it down very accurately therefore on the exact spot required for landing (which was not so easy with the Spitfire). All this time I felt that it could use much more power with great advantage if only it was available."
" The Venom had some interesting technical features: for instance, engine cowling gills,gun heating and gun firing were all electrically operated as wellas the normal electrical services such as reflectorgunsight, navigation lights, cockpit illumination and so on."
"Another point of interest was that the whole engine hinged through 90 deg on ther ground allowing very ready access to the back of it for maintenance purposes, all connections being flexible. From the early performance trials which I carried out it was clear the Venom was breathing down the Hurricane's neck as far as maximum speed was concerned; I was very much fretting for more power from the engine but there seemed no chance of that in the immediate future."