I have been using Dadi Oil for 17 months now. I have converted all my clients onto it to. They will not allow anything else on their nails now. They know it by smell, feel and sight. The transformation in their nails is truly amazing. No other oil I've used has come close to this one. A miracle in a bottle! LOVE IT! I sell the 15ml above any other size. I don't know if a 7.3ml would work for me. I even sell the 72ml bottle to clients because we all believe in the products amazing results.