I like John would suggest you go either with an Overland or a loaded Limited 4x4 (QDII) with the Hemi. The grin you get on your face when accelerating negates the frown you get on your face from watching the price on the gas pump keep going up. Unfortunately, there is no diesel option for the Commander in the US yet, otherwise I would suggest that.
Like jeep5253 said, the only difference is that true 4WD systems come with a low range option (useful on snow packed country roads, for off-roading, and for getting your vehicle unstuck). The QTI system is an all wheel drive system, while QTII and QDII are true 4WD systems. All three are very advanced and very capable systems.