I don't agree that it is much better, since the OP lives in a winter climate, and it is currently winter in the northern hemisphere. Why would he need to go to a 5w-40?

There are also lots of 5W-40 oils that are not 'european car' spec; that oil is used in a lot of diesel trucks.

IMO, the downside to using a wider range oil is that they don't tend to stay within their published viscosity specs as long as a narrower range oil does.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
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