Recently purchased the Panasonic TX-58DX750B TV from Richer Sounds. When I phoned to reserve it for Collection I was told it was Brand New Boxed. However, on reaching the store I was told they couldn't find it, but had an open-box one which they would give me a 10% discount on, making the price £719. I accepted this on the understanding that it was not an ex-display model with hundreds of hours usage. I was assured it was not ex-display. On getting the TV home I had an installer come in to wall mount the TV for me. After mounting it, he commented on the screen being badly marked and asked had I bought it second-hand. On close inspection the screen was filthy and had water marks, as if it had been wiped with a dirty wet cloth, and the rear vents on the TV were very dusty. Called Richer Sounds, who then asked me to send photos of the screen. They agreed it was filthy, but still insisted it was not ex-display, and that they would send me out a free screen-cleaning kit. I strongly suspect this TV is ex-display and was in use for many hours before selling it to me. My question is : Is there any menu on this tv that will tell me how many Usage hours this TV has, and How do I access this menu, as this TV was sold to me in an absolutely shocking condition. Many thanks in advance to anyone who can help me with any advice on this matter.