I'm with Phil on this one, 1/2 litre per 2000 miles or even worse, none at all between services means they just aren't being driven hard enough!! I'd be interested to see how many miles between service the car was going to use no oil. The difference between the full and refill marks on the dip stick I believe is about 1 3/4 litres so in theory, if you were only doing one or two thousand between services it could get away without being topped up. However, for 3000, 4000, 5000 or more miles not requiring any top up at all is quite remarkable. PS I assume that people do use the dip stick, when the engine is fully warm and not rely to heavily on the dashboard oil level which is slightly less accurate. The sun is going to be out this weekend so my recommendation is check the oil level, then go and put a couple of hundred or more miles on it giving it the beans (the sweet spot - 4000 - 6000) and if it still doesn't use any oil, we've waited 2000 years for another miracle but another just happened.