Thanks for the link. I ended up taking the 43" model back to Best Buy and bought a PN51E440 from Sam's Club. I *think* it's essentially the same as the 450's with a Sam's-specific model number (??). It certainly looks exactly the same, but larger. It was floor model on closeout and was pretty much a no-brainer price-wise: less than the 43".
Anyway, having lived with this TV for a couple of weeks I have to say that I now agree with the reference. Watching this TV, even at 51", from 8-10 feet away I can't discern any difference from my 1080p 50" in the living room. In fact, I like this TV more, probably because it's a plasma.
I haven't looked into self-calibrating yet, and have set up the TV to the numbers posted here. I've tweaked them around some, but it seems if I get one station or source looking "best" to me that other stations/sources suffer, so it seems like a chase-your-tail situation at least for an amateur like myself. I've got it set so the NBA playoffs look great now--to me.
One thing I noticed on my other TV, which is a 3-4 year old Philips 50", 120Hz, 1080p model
is they have a guided set-up program where you go through 6-8 screens that are split down the middle and you choose "Left" or "Right" according to your taste. At the end of that the Philips looks pretty good--again to me.
Maybe one of these days I'll spring for a pro to come and calibrate just to see if I'm missing something!
As far as 4K goes...I understand the logic of pixel perception, but I've read so many reviews of people who have seen 4K in person who just rave about it....I guess the original source must make a difference there. Analogous to something like a BD vs. cable TV--there's just way more information in the source?