You're going to need a tuner to calibrate the speedo for any gear swap higher than a 3.31. Otherwise your speedometer will be off and record inaccurate miles.
IMO, your best bet is to go with a CAI/Tuner combo
. You'll feel a significant differences in power and throttle response with this combo. Then down the road when you install a new gear set, you can have the tune's adjusted for the new gears- correcting the speedo.
Plus, if you pick up a tuner from AM/Bama, you'll be enrolled into the Free Tunes for Life program. This also allows you to receive free tune updates for any future bolt-on mods.
Please feel free to send me a PM if you have any other questions. I'd be happy to point you in the right direction!