As title : whilst my MDE 7ltre 300 Bar Bottle still has enough gas in it for the present, it's out of test (dated 2012/05) and needs a new Test Certificate before it can be filled again. I've got another cylinder anyway, so strictly speaking don't need the MDE one any longer. My question is, when's the best time to sell it, as is, or after testing ? and what could I reasonably expect to get for it either way around ?

Thanks in advance for any helpful replies, Vic thompson.