By having Aero Package, your Coefficient of Drag will be reduced to 0.26 from 0.27 and the underbody lift will be zero. You will have higher control and very minimal gain of MPG at high speed operation. Only visual change is the rear spoiler. But for $550, it's worth it. I wish I got them because getting a spoiler afterward is like $800 with installation and everything. Aero Package is totally a visual upgrade and costs over $1200 bucks. I personally don't like the factory kit so if anything, I would go for aftermarket but I wouldn't anyways.

But can you really feel the handling difference? 550 is alot of money just for "stats" and no real world (feeling) difference.

Has anyone test driven both? feel any difference?

Made mistake, Aero Kit does not include side sills.

I don't think I can be able to tell a difference but you can probably HEAR the difference of wind noise. Just think of it like buying the rear spoiler and getting the under diffusers free. I personally called the dealer today to have my spoiler installed and they quoted me 650+tax+200installation so it's over 900 bucks!!!!! I'm gonna get a wing from cheaper dealer and have the bodyshop that I went last time to install it for 60 bucks.

wasn't going to get the rear spoiler.

when i had the JDM STi front spoiler on my WRX, i could feel the frontend sticking
better at high speeds...but that was a HUGE lip.

the lip on my G35C is only for cosmetics.

so the Aero Package is just the lip and the rear spoiler? not sure wat it included
but I looked all over to find a spoilerless 04 6MT and just added the factory lip
myself (for cosmetic reasons).

www.everythingg35.com has them at a great price.

Is the rear spoiler on everythingg35.com a real factory or a replica?? Wherelse can I buy the real factory spoiler other than the dealership??

Those are genuine factory spoilers unless noted otherwise. comes pre-painted.

here's the linky:

http://infinitipa.zoovy.com/product/K6030AM803