I purchased an NX720 at Frys a week ago when they were on sale at $1099. There were none of these on the floor, despite the big ad in the paper for the "major brand name" item that requires one to visit the store...I happened to look up on the warehouse rack system next to the department and saw 3 of them. Salesman didn't really want to sell it to me, trying to convince me I'd "be happier with the Samsung," when in fact, "he" would happier if I bought the Samsung.
Then, visiting Costco a couple of days later, I was checking to see how many of the Panasonic 60ST30 sets they had left at $1199. Answer was zero, but they did have the floor model, marked down to $800. I bought it, after determining through Costco's inventory system that the TV had only been on the floor for 3 weeks.
So, I now have them both sitting side by side, hooked up to DirecTV HD DVR for evaluation. Aside from the size differential, there are other differences that are making this a very difficult decision for me. For those interested in either of these TVs, here are my initial thoughts. I'm not a professional installer or anything; just a home-owner trying to maximize my enjoyment on limited funds.
1. Appearance. The Sony is drop-dead gorgeous. With the frameless design and the Gorilla glass front, turned off, the Sony looks like a glossy, jet black piece of glass hanging on the wall. Beautiful. The "Sony" logo in the center of the TV illuminates from behind the glass when the set is turned on. This feature is defeatable if you don't like it. The power "on" indicator is miniscule in size and not really noticeable. The bezel, hidden behind the frame when "off", is 1.5" on the sides and top, and 2.0" on the bottom. The Panasonic, on the other hand, is their entry level 3D plasma, and it is fairly plain, as others have noted in reviews. The very visible bezel is glossy black, 2" on the sides and top, and 3" on the bottom. The "Panasonic" logo does not illuminate, and the power "on" indicator is a larger, very noticeable red LED. It's not too distracting, but most definitely larger than the Sony indicator.
2. Screen. The Gorilla glass has a slight tint, but it is glossy and slick, and therefore quite reflective. Jet black when off, and when on, the "dynamic" local dimming actually yields an extremely black screen. It's an edge-lit TV, but my understanding is that the local dimming dims half of the screen at at time or something along those lines when the picture is dark. It is very impressive and I have not found any visible line or transition point that would make it apparent if one side of the backlight has been switched off. The plasma, on the other hand, has some sort of anti-reflective coating on the screen. I would call it "semi-matte", as there is still a reflection from the windows on the opposite side of the room, though not to the same extent as the Sony. When the Panasonic is turned off, because of this coating, the screen is not jet black like the Sony. It is more of a dark, charcoal grey. This charcoal grey remains as what you see for blacks when the set is on, watching in daylight conditions. You can tell the black is actually better on the plasma, when the black is floating in the middle of an otherwise bright screen, but for darker scenes, it's muted to a degree to this charcoal grey. During daylight, dark scenes look better on the Sony for this reason. Look at the attached pic I just shot with my phone. Both TVs are on, and the DirecTV screen saver is floating around on an otherwise black screen. Very obvious difference between the sets. This difference is meaningless when watching at night, but very noticeable when watching in daylight conditions. The black level visible in this photo is the same level of black that is visible on both sets when the sets are off.
3. Viewing angle. No doubt about the viewing angle on the plasma. Basically 180 degrees with no degradation of color across the room. The Sony has a relatively narrow viewing angle. I sit approx. 12' across the room from the TV, and color is fine about 4-5' on either side of center, but fades rapidly beyond about 5'. You can tell a slight difference just a couple of feet off center, but it is not significant enough to be a problem until you get beyond 5'.
4. Colors. I have been adjusting both sets to the extent I can based on settings here and on other sites. They are very similar. I would say fleshtones look slightly better on the plasma and maybe a bit more yellowish on the LED. This may just be a reflection of my skills or lack thereof, but the colors are very good on both sets.
5. Motion. The Sony has "Motionflow 240" on this particular set. When watching a hockey game last night on both sets, both handled motion extremely well. Slight advantage to the plasma, but only because I was focused on it. Most would not be able to tell any difference.
6. Little things. Power cord on the Sony is a two-pronged cord, which appears to be permanently attached behind a panel. Not easily swappable for a longer cord for wall mounting purposes. The Panasonic has a strange clip on the OEM plug, but it appears to be a standard 3-prong computer-type cord that can be swapped for a longer cord if necessary. Both TVs have been on for quite a while and both of them remain cool to the touch. No significant heat coming out of the plasma.
7. "Forum" Issues. The Sony is evidently known for having some units where the gorilla glass has separated from the TV housing. Mine did not have this. Nice tight seal all the way around. Also, "flashlighting" and "clouding" on the LED, neither of which I have experienced, at least following changing some settings to get the TV out of torch mode. The Panasonic is limitations including fluctuating brightness and pink/green blobs. As a basic, but very anal user of the unit, mine has neither of these problems. It was a November 2011 build, so that may be why. Bottom line, both sets are great.
8. 3D. I didn't buy the set for 3D, and neither came with glasses, so I can not evaluate this, nor will that be a factor in my decision.
I guess that's about it. I have to decide which one to keep. I wish I could keep them both, but if I did, I'd have 2 TVs and my wife would have everything else. Difference in my cost between the 2 sets is about $325. I'm leaning plasma at this point, only because 60" for $800 is hard to beat and the "bigger is always better" idea is hanging over my head. Plus, a 2-year warranty I can extend to 5 for only $59. But, this Sony LED is pretty incredible, and I can still extend the warranty from 1 to 3 for $99 at Costco, via Square Trade. I noticed they are not continuing this model for 2012. I think they want to keep the Gorilla glass only for higher end models. If the Sony 60NX720 were sitting next to the plasma at this moment, for a similar price, I'd go Sony.
I do have to add one comment about Frys. My experience is that Frys only has great deals for those that are willing to sift through all of the BS to get to what they want, and also those that know exactly what they want ahead of time. The ads almost never state the brand name of the TV for the really good deals, so you either have to go to the store and see, or you have to find out via one of these forums what the deals are, oftentimes too late. And, when you get to the store, very often, the red sticker on the TV says "manager's special," which instantly means you are paying $40 for an HDMI cable, purchasing a bundled blu-ray player you probably don't need, and/or $200 for an extended warranty you could get at Costco for less than half of that price. This NX720 did not require a "bundle" purchase, but if I hadn't known of the ad and the price from visiting this forum, I would have never known to ask about it.
Would welcome any feedback on this, but for those wanting the NX720, my evaluation thus far is that it's a great set. Good hunting nonetheless.