My dad bought his LG CX model OLED tv at a local retailer, and it is the EXACT same CX model that is available at Costco, so as far as the LG OLED models they are the same. LG does have higher end OLED tv's like the GX line so there are different lines available but I do know for a fact that the CX line available at Costco is the same as the CX line available at other retailers. I can't speak for other brands or models.No, no bad experience and there may be a reason why Costco gives you higher protection.
As for the reason is that there is a reason why Costco can offer lower prices. They have sets made just for them with features removed or disabled so they can sell them for less. An example, look at the exact model number of a Samsung or LG TV from BB or Costco. You will see a couple digits at the back end that are different at Costco than from anywhere else.
When I was looking for a replacement TV for my Samsung Plasma, I had settled on the Samsung 75" QLED, that is until I saw the Sony 77" OLED. I saw the Samsung at BB for a certain price, then I saw, what seemed to be the exact model at Costco for about $500 less. I was about to pull the trigger, even pulled my wife into the Costco to show her it and fully expected to walk out with one. But the doubter in me made be wait. Then I did my research and compared specs to specs.
1) The BB version had 4 HDMI input : Costco 3 HDMI inputs
2) The BB version TOS out : Costco no TOS fiber out.
3) The BB version had one refresh rate: Costco had a slower refresh rate.
Granted, both probably had the same panels (can't speak to grade), but the electronics and features were definitely different. Costco negotiates with the manufacturers to seem to give you the same TV for cheaper but maintaining their profit margin. But in reality, they are NOT the same TV. Either B grade panels, components or boards that have had options not installed to save on the BOM (Bill of Materials).
Now for the average consumer, not prosumer, what I mentioned above won't mean a thing as it sits in a regular living room with 12 children watching their Disney channel. But if you are buying a display for the best in viewing experience and for a designed media room, you obviously want the most features, the best picture and the best hardware and signal processors.
So yes, I had the opportunity to physically compare what seemed to be the same model. But then I saw the model number differences and as curious. So I did some Googling (you can do it yourself) and see that what seems to be the same hardware is not.
Again, for the average mom and pop, so what, they saved $500 bucks! Yeah!
For the people that take the time to be on this forum, is $500 bucks worth it?
If you don't believe me, go to your local Costco and find a Samsung and take down the model number, then go to the Samsung site and look up the same set. You won't find that model number but something close. Now compare specs to specs..... Voila!