It's a nice little bump especially if you pick up the Rubi take-offs for a good price. The Sport will be okay with the 3.73 gearing. If you're upgrading from the 16 inch wheels with 29 inch ST tires, you'll need to look into correcting the speedo. You can either go to the dealership to have hem flash it, which can cost anywhere between FREE and $75, or you can pick up a ProCal for $150 new, $100 used. If you have a little more to spend, there's the Flashpaq which will correct the speedo and tighten up the automatic tranny a litte. They're ~$330 new and can be found for cheaper used, but make sure it is unlocked if you buy it used otherwise it will cost you $100 from Superchips to unlock it. Happy wheeling.
'09 X Unlimited, 4WD, auto, half-doors, soft-top
RC 2.5" Series II BB, JKS Quick Discos, JKS adjustable front track bar
15x8 Unique 297 (Soft 8), Goodyear MTR/Kevlar 35x12.50R15
5.13 gears, ARB front locker, Currie front shafts
Bushwacker flat flares, Rubicon rails with steps added