I drive both a 05 Daytona regular cab 4x4 and a non daytone on a regular basis. the other is the same truck without the daytona package. The daytona has a volant intake, gibson exhaust and a superchips intake. the difference in the 2 trucks is night and day. the superchips made a big differnce in the shift points the most i feel. they are more firm and precise it seems. but these are regular cab trucks so im not sure if you will feel such a difference in your heavier crew cab
Thanks im just tryin to get some input before i buy but i am fairly certain one is in my future. I could suggest to you looking up the Vararam Hemi under glass intake, its by far the best intake you can get i put one on my truck with my custon cat back duals and gained around 20hp, also on the vararam site it has a comparo with the volant and the truck with the hemi under glass is quicker.