Ok, here are the low-downs on intakes (please read, good info):
First, you have two types, CAI (cold air induction) and SRI (short ram intake). For the most part, you have two name brands that make intakes: Injen, and AEM. Injen makes the CAI and AEM makes the SRI. Also, you can purchase a no-name, Bomz, or other off brand intake from eBay with simliar results to the SRI.
Rumors: Dispite what a lot of people say, the two types of intakes do not yeild a significant power difference. I have owned both types and noticed NO, NONE, NADA, ZIP, ZILCH increase between the SRI and the CAI. The basic difference is 1) Looks (the Injen you can get in different powdercoated colors), and 2) Personal Preference. The eBay intake will yield almost IDENTICAL results to the AEM SRI power wise. In my opinion, the eBay ones look like junk, but they serve their purpose...I had an eBay intake before my Injen...it's a good intake for a tight budget.
Another rumor is that you will have to worry about the CAI taking in water and destroying your engine...while this is theorectically possible, it will not happen unless you submerge your intake in water (ie - drive through a 2ft deep puddle)...the CAI is hidden in your wheel well behind the plastic shield which is screwed in...if you are especially nervous, you can always get the AEM bypass valve, although I personally think it's a waste of money unless you live somewhere that you may run into that much water (talk to pdhaudio83).
Prices: You are going to spend significantly more money for the Inejn or AEM intake over the eBay intake. And you are going to spend more money for the Injen over the AEM. A lot of owners feel it's worth the money to be able to get your intake in Black, Red, Blue, Silver, etc, and therefore spend their money on the Injen. Frankly, if you don't care about name brands, or care what people think when you open your hood (if you even open your hood), I would not waste my money on the Injen or AEM...but that's just my opinion, and many hours have been wasted arguing this point. Many owners have found the best prices for the Injen at
www.adventon.com...