Not Audi specific but I am conflicted (I don't buy the BS) about car washing products.
The question is: what is so special and different about the store bought car wash products versus dish soap?
I keep hearing about how 'harsh' the dish soap is but comparing cooking muck to road muck, I know the road muck is harder to clean. For tar and real greasy stuff I use an orange based cleaner which works much better than anything else. In fact, only the orange based cleaner will do the job. I also use it on my bike, BBQ and any where else grease and grime build up.
Anyway, so why would a car wash product be any less harsh or better than dish washing soap? I am having a hard time buying into the marketing. Soap is soap, pretty much.
TIA