I want to give my good review of Berryman's B12 Chemtool. I'm not in the mood to write a long extensive review on the product/company but I want to quickly state that they've earned a consumer. After having a somewhat lackluster first experience with their product I contacted them and was pleasantly surprised with the quick and completely professional response I received. After giving them another shot shortly after our communication I was absolutely thrilled with the results. As someone who logs every tank of gas on Fuelly I have a very good idea of what is going on with my fuel consumption, I noticed an immediate gain in fuel economy. I was averaging 13.8 MPGs on my typical day to day driving, after using B12 that number jumped to 14.5. As someone who has never seen/felt an actual difference using a Fuel System Cleaner, I'm glad this product does what it says it will. Feel free to ask me any questions or elaborate on my experience. Kudos to Berryman!