Costco has one of the best warranties on electrical equipment however most aren’t worth the paper they are written on. I don’t want to come across or sound snobish here but, if your nly paying a few hundred quid for a TV and can get the same one for £50 cheaper with only the manufacturers warranty, then I’d save my money and go with the cheapest. I didn’t even consider a warranty free or otherwise on my TV, rather opted for the cheapest I could get it.
Most electrical items are covered by a 1, 2 or 5 year warranty, your also covered by consumer rights and if were all trueful how many of us have had a TV go faulty. There’s also the saying if something is going to go wrong it will manifest itself in the first year where electrical equpment is concened and your unlucjy if it goes wrong after, with most electrical good lasting a minimum of 6 years.