Ok, so I use to have one and sold it b/c I started using Zaino's shampoo and I didn't want to be wasting that much soap. My experience with the foam gun was that it was terribly wastefull of the soap. So am I just plain wrong or is it truth that if you plan on using a foam gun be prepared to run through bottles of soap. My Z7 shampoo normally lasts me 6-8 months using the bucket method.