Had a "quick" look at the 500 and the 50 plasmas (not sure of the full product codes)side by side both showing HD source from a hard drive. First comment both are very very good due to the excellent quality of the HD picture being shown there was little to choose between the two. I could just see the difference in favour of the 500 when concentrating very hard. This was only a quick look and it does not mean that I was disappointed with 500 HD display, no I'm just so impressed with current batch of plasmas from Panasonic. they said they will be getting their 50" HD models any day soon. @£5.5k a little rich for my blood alas.