This product is fairly new to me, but living in So Cal, we are currently not allowed to wash our cars in our driveways. That's a new one as we've always been able to in past droughts as long as we didn't let the water run.
Seeing as there's no way I'm going to drive my car through a car wash, tried some no rinse wash -
Optimum No Rinse Wash & Shine. I've seen this stuff used for years by detailers but even still I've been a real skeptic and never thought I'd try it.
With the washing restrictions not going anywhere, thought I'd give it a try. The paint on my car is bad enough that I could use steel wool on it and it's probably going to make it better. But used this stuff on several other cars now as well and I'm impressed. If the car isn't terribly dirty and you follow the directions, it does indeed seem to clean very well and seems safe on the finish. Sort of amazing / weird to wash a whole car with like 2 gallons of water.
If the car is really dirty or has a lot of stuck on crud, it's more than this stuff can handle. It's seems to be more about lifting the dirt, and lubricating the surface so it's not soap.
Now I'm also finding this to be pretty handy for a number of different things. Like I used it to rinse off my car cover. Did part with just a hose and part with this stuff in a sprayer and it actually was getting more dirt off then blasting it with a hose.
I've also used it to rinse off the engine compartment. It's not a degreaser or even soap as I mentioned so it won't get rid of grease and oil, but really quickly cleaned up the engine bay in just a few seconds without soaking everything and I think better than water alone.
I can see now that I'll be using this for cleaning stuff around the shop and house and not just on the car. I also see that people use it as a clay bar lubricant and a bunch of other uses for detailing. A little goes a long way as well.
Anyway, not a miracle product that's going to change you're lives, but seems like something worth trying even if you aren't under a drought restriction.