It's odd some seem to use oil others dont. Mine uses around 1litre every 1200 miles or there abouts. On a long steady run doesnt use that much. from bottom of the dipstick to the top is meant to be 1 litre, i put about 800ml in and just keep an eye out not to overfill.
When i get a full oil change done out of 5 litres i am normally left with 250ml of oil left in the container.
I always use Vauxhall 5-30 fully synth, seem to run better then the 10-40 semi but uses a bit more.