Six weeks of harsh winter weather are usually enough to reveal which polish is most likely to provide your car with the protection it needs all year round. Because polishing and waxing are among the most time and energy-consuming valeting jobs, durability is important, too. We tested 30 liquids, pastes and sprays, including those from the world’s biggest names, but it was low-profile Collinite’s No476S that showed them all up. Its combination of stamina and protection impressed us.