One of the guys I work with installs Directv, wired security in homes, home automation, etc. afer hours. He supports our big lab infrastructure. The company wanted TVs set up in our buildings and he ended up doing it because the companies hired to do the work flubbed it up. Vizios were installed about a year ago. So far no problems.
What he did say was that they are throw aways which I guess most of this stuff is nowadays. He said that the Costco/Sams stores would accept returns for defects and give you a new tv. But the new tv would hold the same warrenty period. So if your first TV's warrenty was to expire in 12/2010 so would the replacement TV.
Something you might want to ask about if you buy ANY of these TVs.
We have had some Plasma's on the wall for at least 4-5 years without any trouble. Not sure of the brand though.
Me? I am waiting for the prices to keep on falling before we buy a 56-60 inch TV.
Later,
Dan