I have two 5 BBL unitanks for sale, tested to 31 PSI. They are identical in shape and size: ~6’6″x3’9″ and  484 lbs. They are dual-jacketed, drop temperature quickly, and have DIN fittings on the racking arms. There are no issues or damage to speak of. I might recommend replacing the temp controllers; all work fine, but I couldn’t find anything online to troubleshoot them if need be.