A car battery that I purchased from them failed to start a few times over the course of two days. It was in the second year of a five-year warranty, so I took it in for a pro-rated replacement. NTB tested it and said it was fine. It was tested by several other repair places, which said it should be replaced. One said it was "shot" and another said it was the wrong sized battery for the car. NTB would not honor its warranty. NTB either used faulty testing equipment or simply did not want to honor its guarantee. read full review »