The American and European car oil markets are utterly different. Many Americans are still fixed on the idea of a 3000 mile 'lube service' whereas in Europe, a car that will do 20000 miles between oil changes is not unknown.
I will never accept the rubbish about oils being OK for 20,000 - that's just the manufacturers playing to the Which Car Running Costs comparison crowd as far as I am concerned! 6000 miles max or annually is the RINGA household rules and we've had sterling performance from all the cars for years. 265,000 on a 200TDi Discovery and when the cambelt last broke (at 30,000 miles, despite changing them at half the recommend LR intervals back then) there will still zero discernible lip at the top of the bores and it was performing very well. S2000 currently on 112,000 and all the better for regular changes.
Get it from my late father, who swore that oil change frequency was more important than brand/make-up/additives per se. My M3W gets a flush and fresh tank of H-D 20/50 Synthetic lube every 4-5000 miles and will continue to do so :-)
