- gas 
- usability 
- easy up grades
- overall performance
Gas - Yes. They dont sell that many diesels here. Its probably recomended. Dont worry about mileage, its a Jeep. Its a barn on wheels 

Usability - Can you fit your partner and a suitcase with some spare clothes, tools, a recovery strap and a cooler? Yes? Then is usable. 
Easy up grades - Gear down if heavy, that will ease it up most grades....
Overall performance - Its a Jeep. It will roll around corners, bounce over potholes, and creak, groan and whistle. If you want the most offroad capable vehicle sold in North America? Then it will perform!