Diesel can be more fuel efficient. However, diesel usually costs more at the pump, and diesel variants usually cost more to purchase up front, so unless you are doing big kms, you won't really get much monetary benefit from going diesel over petrol (assuming the model you're looking at has both options). Personally though, I like the current range of diesels. Plenty of torque at low revs. Perfect if you are going to be doing any regular towing, or perhaps carrying a few sandbags around.