Just got a brand new w204 in white it's got a little dirty what's the best way to keep it clean in between washes? Are the waterless cleaning systems any good?
You'll swirl the paint like mad if you use that stuff and you could save a fortune by just using pledge furniture polish since its very similar.
Best thing to do is to get it decontaminated, polished, glazed, sealed and waxed then when it's dirty you can quite literally hose the dirt off then drive the car to dry it in between washes - I regularly do that with my car.
For me I use a mix of products, CarPro, Valet Pro, Dodo Juice, Chemical Guys and much more. All down to preference really but loving Chemical Guys stuff at the minute so easy to use and the results are great too.