Some people dont have that luxry mate, and at shows, or when you live in a flat with no water outside, then ONR is a god send. I dont use it, like JD said, have garage, driveway and a tap that water comes out of ....
I dont have a drive way, tap, garage, garden to help me clean my car.
I go to the local jetwash about a mile away, wash the car off completly and drive home. Two buckets out and wash over the car again with a final rinse off with demon shine in the bucket using a sprayer then use some wax on it once its dried.
I will never use anything like this stuff, id prefer to fill a hippo roller with water and drag that to the end of my road and clean the car.
Hippo Roller - carries about 90ltrs or 24gallons of water.