alum airbox questions/suggestions

[mcwilly]

Originally, I was going to go w/ the outerwears lid on my stock airbox. That way I get the maximum performance out of the airflow. But the more I got to thinking about it, the more I wanted to go w/ an aluminum airbox and replace the battery from under the rear fender. Insane performance offers their alum airbox w/ a vented lid. Do you think I'd see a difference in performance running the vented lid on the aluminum airbox vs. the stock airbox w/ the outerwears lid? My only concern is water protection w/ the alum airbox. Does anybody make an alum airbox that can use an outerwears style lid?
Here's the airbox w/ vented lid from insane performance:
http://www.insaneperformanceatv.com/400EX1.gif

[Jnblaster05]

im not totally sure but i did just buy the box your lookin at from insane performance and will have it shortly and let you know if theres much of a gain the box is really profesional though