There's a ton of threads on this forum that will answer both your questions with more info than you'll ever need. I'm referring you to past threads because everbody has their own opinions about exhaust (I have a Dynomax cat back) and the prevailing thoughts on CAI's is that they are worthless (to each their own). In short use, the search function.
and like rubi said, general consensus is a CAI is a waste of money so dont do it. There are valid arguments for both sides so choice is all yours. Try goin through the search button and see what you can read up on. Reading tons of previous posts will give you a better idea than waiting to see what people have to say.
I personally am getting a new magnaflow muffler (always been a fan) and have a drop in KN filter...so far i've only gone one tank with the filter in and it seems to breath better and there are areas where i once had to downshift where i no longer do, but i also got 10 miles less on the tank. Coulda been because there was about 100 miles less hwy driving this time around.
Biggest concern about going with a CAI is the amount of debris that will be let into the intake tube and into the motor...all gonna be up to you!
clean jeep though, man...really like that (bra not so much, but the overall look makes up for it)
i have a 2.5 and have the banks and it sounds great, my buddy has the banks in his 6 and it had a good tone to it, but its all just preference. the banks muffler is a straight through design with a 2.5" pipe rather than the stock 2.25" pipe, and its stainless steel.
Dear Algebra, Please stop asking us to find your X. She's never coming back and don't ask Y.