Ours is a 2004 65325 (I think thats the model number, I believe. It was the first year of HDMI, which I haven't used.). We also had the prior years model, probably 65315 (no HDMI), which we sold.
I like the Mits fine. I don't have the two side by side, so it is very hard to compare. For the money, I don't think you can beat the Mits RPTV for the money, but the WAF was very, very low due to the bulk. I wanted to get the Sony XBR2, but my wife wanted a wall mounted unit. Therefore ....
I compared the Pioneer and the Panny. The Pioneer is great, but expensive. So, I chose the Panny 58". I would say that SD is not quite as good as the Mits. HD is the same (even though we are talking 720P vs. 1080i). I have the D* receiver set on 720p, haven't experimented with trying 1080i or other resolutions. I really haven't watched enough DVDs yet to compare fairly. Using OPPO 971 upconverter, I would say so far that the Panny is the same or slightly less. However, that is only based on watching 3 movies! Not exactly scientific. I am also slightly prejudiced, since I really liked the Mits.
For sure, I would say that the Panny absolutely does not blow the Mits away. However, even for twice the dollars, my wife loves the Panny hanging on the wall. Enough said???