Well I had a small leak in my radiator and you all probably know that one can no longer be found via Audi or aftermarket. Found one in Calgary with fellow RS6.com member who parted out a car. When adding up the costs since I don't wrench myself, I decided to give LiquiMoly Radiator Stop Leak a try. Not one drop has leaked since then. Really surprised how well the stuff worked, but if you are in the same boat I was in, consider giving it a try before sinking $$ into a new radiator.