I know there have been a lot of threads like this... but they normally don't reach a definitive conclusion and since there are new models out that change the options available, I thought I'd start a new one...

I'm debating between the Pio 5080 and the Panasonic 58PX60U & 58PH10UK (and perhaps the 50PZ700U as well). For the most part, these are all roughly in the same price range -- except perhaps the 58PH10UK after accounting for the cost of HDMI blades.

The length of my room where the TV will go is 12 feet -- my viewing distance after accounting for the back of the couch and for where I will likely mount the plasma on a pedestal would be about 10.5 to 11 feet.

As far as the two 50" sets are concerned, the Panny of course does 1080p, and seems to have better contrast than its 50PX75U/77U siblings -- but at 10 feet or more, that extra resolution may go unused unless I pull a chair up to the set for playing games (might reduce SDE if I sit closer). The downside is that it only has 2 HDMI inputs and no VGA.

The Pio seems to be regarded as having the best PQ in the <$3.5k price range regardless of size. For those who have done fair comparisons (I can only see them in brightly lit BB showrooms), is the Pio head and shoulders above the 3 Panasonic sets I mentioned? The Pio also has 4 HDMI (v1.3) & a VGA (which I would use for the Xbox 360), so this is quite an advantage in feature set. Both 50" sets get a small bonus for being lighter and thus easier to mount.

If I spring for 58" I'll definitely go with one of the Panny's to stay within budget, but I'm concerned over whether the extra screen size at 10-11 feet will make the display seem less impressive vs. the 50" at the same resolution, as I'd be able to see the benefit of 1080p in a 58" at this viewing distance (I think). I'm concerned that neither the 60U or 10UK will have quite as good PQ as either of the two 50" I'm looking at. But again, I need some advice as to whether this will be the case. Both of these sets also have inferior features to the Pio -- and I'd really like to be able to pass through audio signals via HDMI through the TV to my receiver.

Assuming the price is a wash, and you're viewing from 11 feet in a room where you can control the ambient light most of the time, which of these would you go with -- strictly judging by picture quality, features, & size?

I would and did go with the 5080 in a similar situation, although my room differs in that I have a secondary seating postion that is closer for gaming, which was also a factor. It sounds like you have a very good handle on the trade-offs involved and have considered most of the relevant factors.

For me, it came down to the 5080's blacks (which help quite a bit during nighttime viewing), the ability to drive native resolution through VGA and HDMI, and the processing. I have never been very impressed with the processing in the Panasonic 50 and 600 series panels that I have seen in the homes of friends and family even after I played with the settings to help them calibrate them. The processing in the 5080 seems more flexible with respect to fixing source deficiencies and reducing mpeg artifacts. In my judgment, the performance of the 5080 is more setting dependent that most models; out of the box I was not very impressed, but with a little tweaking was very satisfied. I saw one in a store the other day and it didn't stand out that much from the other panels in their lighting, but it looks better in my home after tweaking.

I would readily take the quality of the 5080 over the size and processing of the 58" Panny 60 series. With the bigger panel, you will see more of the warts in your source signal, and most sources, even much of the OTA HD, do have warts. If you do go for a 5080, I recommend setting it on a stand instead of wall mounting, because the stand will bring it a few inches closer to your seating position. Not a big difference, but every little bit helps.

At eleven feet away I wouldn't consider anything less than a 58" screen. (That's me, however. I sit eight and half feet back from a 65" set and wish I had a 70" set.) A 50" screen will certainly look less impressive than a 58" screen at that distance. And I don't feel that the Pioneer video quality is "head and shoulders" above the Panasonic sets. As you stated, the feature set is better on the Pioneer so if that is crucial to you...otherwise, I'd vote for the 58" Panny.

I'd choose the 6070 over both at 11-feet. I saw all 3 a couple days ago, and at 11-feet,
the 6070 actually looks better (and is slightly bigger) than the PZ700. They're about
the same price nowadays. Even further, if you can find a cheap 1540, go for that.

This viewing distance calculator (http://www.myhometheater.homestead.com/viewingdistancecalculator.html) might help as you ponder. This chart (http://hdguru.com/wp-content/uploads/2006/11/hdtv_distance_chart.pdf) shows the optimal distance for various sizes and resolutions.

One thing that is rarely mentioned is the relationship of screen size to program material. While it is axiomatic in these forums that bigger is better, that is not universally true for everyone. Movies and sports generally benefit from an immersive large display, but many people find regular TV to be a bit overbearing if the screen is "too large." These shows are produced with viewing smaller screen with a heavy reliance on close ups that some find uncomfortable to view when enlarged excessively. Not everyone likes a large screen for these shows, which is worth considering if they are what you usually watch. In addition large screens don't always fit the decor, and can dominate a room more than you would like.

FWIW, my experience was much like Assayer, although for me it was a close call between the 5080 and PX700/750. (Found a fantastic deal on the former, which pushed me off the fence.) My preference was for PQ in any case, but we all differ on our priorities.