Don't be fooled by the jargon, spin and outright lies. Make sure you get the best TV at the best price.
Using the time-honoured tactics of obfuscation, misdirection and a little bit of fear, the people who try to sell you TVs can hit you with some heavy-duty lies.
Now, this isn't to say that all TV salespeople are bad, nor that any necessarily do this out of malice (there's plenty of misinformation out there confused as truth). But when it's your dollar on the line, being prepared with some facts can only be a good thing.
This TV has a million-to-one contrast ratio
No, it doesn't. Every TV manufacturer lies about contrast ratio. Not a single one is remotely accurate. So it's impossible to prescribe an exact number to any TV, given only the manufacturers data. The fact is, plasmas have better native contrast ratios than LCDs (LED or otherwise). There are some local-dimming LED LCDs on the market this year (such as the Sony HX950 and LG LM9600), and they're all extremely expensive. These offer similar contrast ratios as the best plasmas, though not exactly. There's some more information on contrast ratio here.
This TV has better sound
You know what, let's say that they're right. Let's say TV 'A' has better sound than TV 'B'. The fact is, no TV sounds good. So all they're really saying is, "This TV sounds less bad than this other TV".
The thinness that we all love in flat-panel TVs means that the speaker drivers, by their very nature, have to be very small. Small drivers can't do much to create sound waves.
The wiser salesperson will direct you towards a sound bar or other home audio system. This is definitely where you should spend a few dollars. Pretty much every sound bar will sound better than the TV speakers, and the better sound bars actually sound pretty good.
TVs break all the time; you need an extended warranty
Another example of this is, "I see TVs come in for repair all the time". From a rhetorical standpoint, this is a brilliant argument. This person works at the store. They see lots of TVs coming in for repair. So, as an "authority", this seems like a valid point.
Except, it isn't.
What the salesperson isn't seeing is all the TVs that don't come in for repair. Which is most of them. Flat-panel TVs are very reliable, so an extended warranty is largely a waste of money.
LED TVs have the best picture quality
Nope. First of all, there's no such thing as an "LED TV". Every LED TV is just a standard LCD TV that uses LEDs to create light instead of the "old-fashioned" cold-cathode fluorescent lamps (CCFL). LCDs have their positives, like light output and lower energy consumption, but when it comes to a direct picture quality comparison, plasmas have better black levels, better contrast ratios and better viewing angles (for those not sitting directly in front of the TV). For example, four of the five TVs that CNET picked for best picture quality are plasmas (the one LED LCD is also the most expensive TV you can buy per-screen-inch).
There's more to it than that, and you can readfor a bit more info.
If you want the best picture and sound, you need the best HDMI cable
This is the one that annoys me the most, and I've written four articles about it for CNET alone. This is the one that eliminates any guilt I have impugning the good name of some hard-working salespeople. There is no picture or sound quality difference between any HDMI cable. None. At all. So if you spend $3 or $300, the image and sound will be 100 per cent exactly the same.
I could talk about this forever, and indeed, I have. Check out "Why all HDMI cables are the same", "Why all HDMI cables are the same, part 2", "Still more reasons why all HDMI cable are the same" and the "HDMI cable buying guide".