I set up a car wash in West Quay, Southampton, for a company doing the same thing.
Versus the drive thru car wash, you not going to do any harm. If your a diy detailer you are going to ruin your finish. Half the trouble is the people I had working for me who didn't understand about paint, and easily you can damage it. Hence I had to do all the high end motors myself.
As for Eco it is, uses about 1 litre of water to be fair, compared to car wash, etc it is very good on water, very big in Europe where you can't wash your car on the street.
As for health and safety the shopping centres love it to slips or spills, and you can wash anywhere as no chemical run into the drains.
Would I wash my car using the system? No!
