Why buy a Sony Plasma they are rubbish (IMHO). My brother had a 42" one and it blew up in 4 days and had terrible solarisation. Sony never made their own just used cheapo panels from others and since have pulled out of the plasma market to concentrate on LCD's which they are better at.
A quick check show them being £5k... if you are thinking of spending that kind of cash... the 50" Pioneer or a panel & scaler would be far better way of going...