I bought an ex demo 55" Samsung smart TV from PowerBuy over 4 years ago now and absolutely no problems.....you were unlucky.
A few years back my LG Microwave went tits up....magnetron failure...after 18 months use....bought a Thai brand Midea replacement still working fine 3 years later....do I slag off LG no....it was just bad luck....wind your neck in there are far more things in life you should worry about.