Hmmm now I'm confused, this is from Castrol (taken from an archived thread on driver):

EDGE 5W-30 - this meet the latest BMW LL04 - can be used in any BMW apart from the M3/M5, and I would recommend this for all cars listed above, but especially for petrol cars after 2004 and cars with diesel particulate filters fitted as this oil is classed as low SAPS ( low ash for DPF equipped cars ) and is the nearest retail oil to the BMW dealer product. Probably the best oil to keep in bulk for service fill.

EDGE 5W-40 / EDGE Turbo Diesel 5W-40 - meets BMW LL04 so can be used for any cars - but probably best for older cars with higher mileage and some wear where some oil is being burnt - this offers the enhanced performance of a full synthetic - but with a thicker viscosity to help with oil usage from wear - this is also a good product for cars that can use the EDGE Sport 0W-40 and has an extra lubricity additive for excellent top end protection. Probably the best oil for older cars with high mileages.

So would I be best using 5W-30?