Alright, so the results are my fuel mileage has increased by 1 to 2 mpg. I got 20mpg with 15% towing 25% city and 60% highway driving. The city and trailer towing was not conservative at all either. Smoke is minimal with the edge on 1x1 and about a 6 on 5x5. I love them and will let you know if mileage is any better once the newness wears off.