Dave: 2006 Toyota Sienna 100K 16.9 base line. On my van as an example I just added product in on my 8th tank and calculated the average MPG's on my first 7 with product to get my numbers. At the current price of $3.99 I'm getting 94 more bonus miles out of one tank. After the cost of putting in the product per tank I'm getting back $19.79 per tank in in creased mileage. This translates to 0.9895 cents I'm paying less at the pump per gallon. Roy H : 6-10-12: Dave, I have a Yamaha 99 Grizzly 600. 8742 miles on it. Runs like junk, back fires, and fowling plugs. 11-18-12. Took the plugs out and they are clean. No more fowling and running smooth with more power. Peter A : 6-13-12 My own test is going well and although I haul heavy loads (licensed for 63500 kilo's ) on bush roads, gravel road and highway, I am using less fuel, approx 50 litres less so far and I feel the engine is running smoother with more power!  7-28-12: I am happy with the results so far and will continue to use xp3 in my tank. I have put some in  my lawn mower as well and the old thing seems to be running like a top now! I also have it in my outboard motor and although it is running better. I have been using it in my old out board motor boat and in my lawn mower. The lawn mower just runs like a top now that I have had the xp3 in there for about a year. I had started with sea foam,but it only did so much and when I switched to xp3,the mower improved running about 100%.