How does it seem to get more air to the engine? Have you done any flow measurements?
The purpose of an air filter is to filter out contaminants. "performance" filters like this gain their "performance" by filtering out less, allowing for *marginally* more flow. This is the reason why you see some racecars who have no filters on their intakes at all, most often seen with turbocharged import cars.
An exaggerated analogy would be replacing your stock air filter with a wire mesh screen. More dust/dirt/water/whatever will be sucked in through the intake.
As was said above, it's bad for your engine because those crappy filters do not filter well at all. Put the stock filter back on.
