I bought a couple of S30 cylinders when using the Hambleton Bard valves on my King Kegs. As I no longer use HB valves and the cylinders I contacted my local homebrew shop (where I bought them originally) to ask about returning them for a refund. I was told I’d get “about 4 quid for each cylinder”. Anybody else returned an empty S30 Brewgas cylinder for a refund?