I usually wait for the Valvoline 5W40 MST to be on sale at Napa for around $5 / qt. They typically do have to order it in, though my local Advance Auto started carrying it and will price match.
It's nice to an option from Pennzoil.

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2010 X5 3.5d: SOLD, but miss the torque...
2004 X5 4.4i: SOLD, but served us well