I'm very surprised that you didn't like the plasma picture quality....you sure RS has it set up properly?
My dad was after an LED tv, but as he watches football, F1 and other fast moving programmes, I persuaded him that a plasma was the best way forward....
He has a 32" Panasonic LCD tv too, but finds the TX-P42X50 very good indeed....especially with HD channels, even though its only an 768 resolution screen.
As you will see, I have the same spec Panasonic plasma from 2008, and I think its great with freeeview HD as well as SD tv, as less upscaling is needed compared to a full HD screen.
By the way, he got his TX-P42X50 set for £320-330 (don't remember exact price), delivered and with a 5 year warranty. Must be bargain of the year!!!