Hi , I would like to stand up for john hemmens , I have used his products for over 10 years and have only had the highest regard for his customer care. He has excelled him self in resolving issues concerning a custom built/designed boiler for myself , and by his own admission got it slightly wrong the first time . but the end result is a first class piece of quality engineering , which drives my two 10mm x 12mm slide valve engines fitted in an exact scale model of HMS INFLEXIBLE perfectly , giving more than enough steam to drive the model . The model is nearing completion and has had a wet bottom! . As far as i know john is constantly looking to improve on his designs and relies on direct customer feedback , as he has often said to me if he dosent hear about problems he cant rectify them. So come on lets have a bit more respect for manufacturers as we would be in a poorer state without them.