I know Stryke and I are in total agreement on this one, since there have been similar threads on this topic before. I agree 100% with what he said.
Basically, you want to use as little effort (i.e. energy in any form) and chemicals as possible.
If your car has a good finish and has a good coat of wax, keeping the car clean is very easy. When my car gets salty or dirty in the winter and my hose is turned off, I take the car to the do-it-yourself wash bay style car wash up the street, and only use the super low pressure setting (basically a mist) that is supposed to just kind of get the car wet. Nothing else!! When the car gets wet, all the crap just kind of falls off with no effort what so ever. I then pull the car to the back of the parking lot and give it a good drying with some micro fiber towels and it’s done.
Once you get the car super clean (or keep it that way from the start) and get a good coat of wax, it takes almost no effort the keep it clean.
Few cars in the world look as nice as a Porsche (especially black ones
) when they are spotless, its worth it.