I'm the opposite, I LOVE my Plasma used with SD sources. I think the trick is the scaler used. That Sony is very much old tech and the scaler inside it isn't very good. We have the 50" version here at the office and if I hadn't gotten it dirt cheap ($2600 18 months ago) I wouldn'tve bought it. Limited input options, limited usability, etc.

IMO you can get a brand new current tech ED panel for about the same price like this. I think ED panels are great value if most of what you watch is SD. IMO they look great in HD although not quite as impressive as an HD panel. They ARE HD compatible (at least the one linked is). They just can't display the full resolution and downconvert the image for display.

A CRT HD display has somewhat the same problem although they aren't fixed resolution devices. While a CRT (direct view tube TV) may be able to accept a 1080i or 1080p input, the maximum displayed resolution won't equal 1920x1080 pixels of resolution due to limitations in the way CRT monitors work.

Still, at 42" unless you're right up on the panel you won't miss the difference and I think the ED panels look better at SD resolutions. That Panny 8UK is a GREAT display for as cheap as it is. Speaking as someone who went from a 32" Panny LCD (TC-32LH1) to a 42" NEC Plasma (PX42-XR3A), I'd never go back.