I've spent about a month now with each tv. I had the Panasonic 50PZ800U first, and I was not enjoying it. And now I've been watching the
Pioneer 5020, which I spent a bit more on, not painfully much more, got a pretty good deal on it... I am REALLY liking the 5020, day after day.
Now, what I'm gonna say here about the color, everyone will tell me I'm crazy; I absolutely don't care--I know what I see. The Panasonic emphasizes green, and the Pioneer emphasizes yellow. In skin tones, usually on faces that are a little shaded or around the shaded edges, is where you can see the difference. On the Panasonic, I tried and tried to adjust the green back down to normal; could not get it down without making the picture look bad or otherwise wrong, tried every setting I could find on AVS, bought a calibration blu-ray (which by the way you can rent from Netflix, wish I'd known), did what I could... still, too many faces look too green, sometimes ridiculously so. Could not get through a movie without being annoyed by some strangely colored faces. Had a Best Buy guy (complete a-hole) come out and act like I was crazy. Had a Panasonic guy (very decent guy otherwise) come out and tell me it looked fine. Fine, both of them would probably be motivated to say just that, anyway. Went to Best Buy and saw a Panasonic plasma right next to a Pioneer plasma, same source, glancing back and forth from one to the other, and sure enough, the Panasonic shows subtle greens in a lot of the dimmer, maybe more color-ambiguous parts of the image, where the Pioneer does not, although I noticed the Pioneer showed a little more yellow.
I did the exchange anyway, brought the Pioneer home and tried it. First of all, using D-nice's reference settings pretty much took away all of the excess yellow I was seeing. Second of all, the Pioneer's yellow didn't look anywhere near as bad, to my eyes, as the Panasonic's green. Yellow just kind of adds a bit of sunny warmth a lot of the time, whereas green tends to make a person look sickly. But again, the Pioneer reference settings brought those skin tones to absolute perfection--thank you D-nice!
Now, on that color issue, I've said I absolutely know what I see, but I would also tell someone trying to decide between these two sets that maybe, to the same extent that people would try to tell me I'm just seeing things... most people would not notice. It certainly is usually subtle, but I don't understand how something somewhat subtle would be overlooked by people spending thousands of dollars and so much time learning about so many very technical specifications. It sure mattered to me.
Overall, I am really happy with the 5020 over the 800U, even though there are a few areas where the 800U seemed to perform slightly better: with an SD source; and also on some motion things, like a panning camera... on the Pioneer, panning is a bit more troublesome sometimes... motion is a bit more jerky. Not a lot, but maybe just a bit. Also, once so far I saw weird flicker on an HD source, and I've seen in these forums that some other people saw some flicker, but that was only once, and if you use 24p on the Panasonic, you get plenty of flicker, too... And the Panasonic seemed to do just a bit better job with SD sources, but even though I watch a fair amount of SD (how can you not if it's your main tv?), that difference isn't really much. It certainly isn't enough--none of these factors is--to make me prefer the Panasonic.
And the SOUND on the Pioneer blows the Panasonic away. I wasn't counting on that, but now, if I'm just watching tv or my Netflix set top box (which often means tv series), I usually just use the Pioneer built-in speakers instead of my surround sound system. It's sweet.
One last thing on the color... I've had some people tell me I'm crazy on this other aspect of it too, but then when I was in a store and pointed it out to people, they couldn't really deny it... look at the blank screen on the Panasonic plasma, versus on either the Pioneer or on most panels in general... In certain lighting, under the halogens at my local Best Buy or if natural light is hitting the screen... it doesn't look black; it looks green. During actual tv or movie viewing even under those lighting conditions, the dark parts of the image for the most part don't really seem green because of the context, but if you compare that perfectly black border around the panel, to the supposedly black part of the image right next to it, you can see they aren't anywhere near the same color, and it's not like grey versus black; it's like GREEN versus black. Whereas the Pioneer blacks, and its blank screen, are beautiful and deep. So on the Panasonic, if blank = green, how could that not come out in the images you're trying to watch? I believe it does, I don't care what CNET or anyone else says.
To sum up, I love my Pioneer 5020 over the Panasonic 800U, mostly because of the color, which looks way more accurate on the Pioneer. HD on the Pioneer is exactly the experience I was looking for.
Sincerly hope this helps someone trying to choose between these two panels.