Certainly, wiping down your dash with a damp cloth is the safest way to go, most dashes are meant to put up with a bombardment of UV rays. However, over time the vinyl on your dash loses plasticizers. Plasticizers give your dash the softer touch, over time these evaporate out of the plastic, when they evaporate (ususally the vechile is 10+ years old) it can make it more prone to brittleness and cracking. Water based vinyl protectants will kind of rehydrate the dash, and block out a lot of the UV rays. Any of you who owned a certain type of new car in the early to mid nineties might be fimilar with this "vinyl fog" that accumulated on the inside of the windshields. Its not a big deal for anyone planning to keep their cars for only a few years, if you plan to keep it much longer, than regular usage of a water-based vinyl protect can be a good investment. Whatever you use (water or a water-based vinyl protectant) stay away from petroleum based products, they are not good for the dash and make it look cheap!