The chanca piedra I have always bought from them. I used to buy the tincture and one time they sent me a free bottle of capsules, because they were out of tincture, and later they sent me the bottle and never charged me extra.
I follow now what it says on the bottle, but when I started in the beginning I think Andreas told me to do 20 drops 3x a day.
The GCG you can buy from sensiblehealth.
Now I use the capsules, just easy, and Andreas said that was ok.