Maybe a 6-7% gain in car mileage after magnets applied.

Maybe a 16% gain in natural gas furnace and water heater efficiency...partially
due to other changes with the furnace though.

More or less no difference as far as lime buildup with household water
lines....might possibly rearrange the magnets at some point.

note: since almost no one else has posted any results...this is only from my
own testing so far.