Unless you need to shave a few 10ths of a second off your 1/4 mile time you need to consider the function of the air filter.
If you go for the "Aftermarket" air intake, you lose A LOT of filtering capability, so you really risk getting your engine crudded up shortening its life.
Don't take my word for it, many others have looked into this and came to this conclusion. Here is another forums great web read on this.
NICOclub.com Air Filter Thing
Bottom Line. (See Below)
=----> NOT Recommended. <----=