[surfbeast]

Depends on the application. A stock car witha stock air intake= No big deal, with a cold air kit = some increase, with all the other mods = Chip, exhaust, nitos/blower - it helps the most. Remember the stated 15 Hp gain is flywheel at optimal conditions. To the street Hp gain is only about 10Hp at best. The meter is best when used in conjuction with the other intake parts.

As far as best place to order, any place from the mags that advertises the cheapest price!!