I also purchased the complete package from Banks, the CAI, iQ, and 6-Gun. Installed the CAI first, no issues, looks super clean, fit is great. But no real gains to speak of, and no additional turbo-whine, which I would have preferred. Never threw a single code after install.
Now, for the iQ and 6-gun. I know this is a quality system, and Banks is a quality vendor, but the 6-gun would not work on my truck. I installed the unit, tried to calibrate the trans starting on level 2, and engine lost all power. Ran like it was in a 'safe-mode'. pulled the inline fuse going to the tuner module, and truck ran like stock. Spent 3 months on the phone (3-4) hours a week with banks tech support. First 3 guys i worked with were not helpful at all, then they transferred me to a tech that knew the PS6.4 and he was very helpful. They sent me 3 wiring harness', three 6-gun modules, did countless diagnostics with them over the phone (as much as can be done over the phone)... and the unit would still not work. I do have confidence in Banks, and if I had been local to their shop, they would have worked with my truck to determine the root cause. But, unfortunately, that was not possible, and they were quick to refund 100% of my purchase price.
I am still unsure what the issue was with my truck, and the 6-gun, but it would not work at all. I really really really wanted it to work. So, as a result, I have yet to make another vendor purchase.
Hope this helps with your decision, though my experience was not great, Banks did what they could do to make it work. When the day comes to get another truck, I will still have them on the top of my list. Good Luck!