What are the benefits of upgrading to a performance air intake in a Ford Focus?

I've been considering installing a performance air intake in my Ford Focus but I'm not sure if it's worth the cost. Can anyone explain the benefits and if it's worth the investment?

Replacing the stock air intake with a performance one can increase horsepower, torque and improve acceleration. As for cost effectiveness, it may depend on the type of driving you do and your personal preferences.

Installing a performance air intake can also improve fuel economy, as the engine won't have to work as hard to get air. However, the gains may not be significant enough for the average driver to notice.