I just completed a 9,400 km (nearly 6,000 mile) road trip. The car was fully loaded with three adults and baggage for three weeks on the road.
Driving was extremely varied - a lot of backroads through Ontario, MI and MN, some slow city driving, Interstate travel through SD (speeds around 85 mph with long bursts into triple digits) and mountain roads through the Black Hills, Wyoming and Montana. It included driving through snow at 9,666 feet in Big Horn National Forest - glad to have X drive! Then Banff and more high altitude stuff until long fast roads across the Prairies, ending with the rugged terrain around Lake Superior.
Couldn't find much 93 Octane so 91 had to do. Mileage was 9.4 l/100 kms or 25 mpg (US) or 30 mpg (Imp). The car ran flawlessly with the only problem that it now needs wheel balancing.
Oil consumption was virtually nothing. The car has 20,000 kms (12,000 miles approx) on the original oil and has used about a pint or half a litre - the oil level is roughly midway between "Min" and "Max". I have never added oil.
My only beef with the GC is it's behaviour over potholes - it really crashes and shudders. Otherwise the handling is exemplary, the throttle response is addictive and I could drive (one day!) a thousand kilometres without being unduly tired.
A great car!
