No matter what insurer you go with, make sure they will cover you anywhere in the country, Beach, Bush Water Crossings, Deserts, etc. Obviously, they don't cover private property.
Mods are another thing to take into consideration, will they replace or pay out for all mods to the vehicle.
Towing is something to look into, if you are stuck in the middle of the bush miles off the main road will they foot the bill for recovery/towing?
Transport costs, will they cover all transport coats in the event you vehicle has to be transported back to the city?
Transportation costs, will they pay your transportation costs to return home?
Accommodation, will they pay for accommodation out in the country?
Hire car, do they supply you with a hire car?
New for old replacement in the first 5 years.