I love plasma but unfortunately the mfgs felt they were not selling enough and stopped making them--
at least Panasonic and Samsung have
Consider two factors--
how much light will get into the room where/when you will be using the new tv and
how do you normally choose your viewing material--pretty much straight cable tv shows or do you use streaming sites like Amazon, Hulu, YouTube, Netflix--
or play lot of DVDs
Personally we have gone from watching movies on DVDs and gone to streaming--using Amazon, Netflix, Hulu+, YouTube for the most part --with some rented OnDemand via cable--
I am Amazon Prime and use the video aspect of that and have just discovered Hulu+ which I love for the available BBC/UK television series I can get that aren't available on other sites
In Texas we have an older format (6 yrs old) Samsung 72 flatscreen--not smart--paired with a newer Sony blu-ray dvd smart player--had to replace the older model when Sony stopped updating it and it needed a firmware fix--
we have a Panasonic plasma my husband uses for his XBox gaming and a 46" Samsung in master bedroom
We also bought a smart Samsung 36" inch flatscreen w/wi-fi connect to Internet to use in guest bedroom with a UVerse cable box--it get Amazon, and other main sources and apparently has strong connection even though our router is downstairs...the DVD for that tv is older and not smart but rarely used anyway and we needed a larger screen
In FL vacation house we have Samsungs--and also the smart Sony DVD players--main one is Samsung plasma 52"--my husband wouldn't spring for more $ Panasonic since we were not visiting as often when we first bought that television...now that we are there for longer times and more often, he would probably spend more.
I use a Samsung 720/60hz set in the bedroom that my husband won at golf tournament--and paired with a smart Sony blu-ray dvd I can watch pretty much anything but football w/o really having quality issues--
but maybe I am not as picky as you might be
I agree that it makes more sense to buy a good quality DVD player w/smart feature or maybe something like a Roku if you can find a good quality large flatscreen w/o smart technology at a good price
check Cnet ratings and also site
TV Size to Distance Calculator and Science
I found that when shopping for new 48" flatscreen for our daughter/SIL for Christmas--and thought the info was very unbiased and informative--
they wanted flatscreen for second living area where she could view while in kitchen and toddler could watch cartoons w/o using main tv or going into bedroom
We bought a 48" Vizio Eseries for several reasons--one of which being that they didn't ask for it until close to Christmas and our shopping sources were limited by then w/stores out of stock for ones I might have preferred...
While the Vizio E series might be ok for second tv I wouldn't pick it for main viewing location or pick one of the large screens--too many issues with poor quality/performance/durability