The ECOSSH408 has not only heated our upstairs office to a temperature higher than expected and therefore more than satisfactorily, but it has contributed to a warmer first floor of the whole house. The reason that I did not allocate more than an 'Acceptable' response to your survey, however, was due to the advice I received when I asked (I think to both manufacturer and supplier) "what KW output do we need for our space". I was simply asked the standard questions: what cubic area; what area of glass; how many outside walls; whether cavity filled etc. On each occasion I explained that the building is timber frame construction, double glazed, heavily insulated and includes a Motor Ventilation Heat Recovery system, all accepted methods of new-build schemes. On each occasion I was given the advice, to buy two 408 heaters. Had I followed this advice I would have paid twice as much as required and would no doubt have had too much heat. I do recommend that your staff are brought up to date about the latest building construction methods. Otherwise, I think your product is excellent and I think you should advocate the technical and economic advantages of this purchase in more detail.