I just have a bad feeling about Mobil - why are the UOA not superior, no explanation for raised iron. I prefer something that I can trust, like even Quaker State Ultimate Durability. Even ST synthetic gives excellent UOA at 12,000 miles. My own recommendation for a LONG trip, would be Castrol Edge, 10w30. Even though we all hate Castrol's marketing, their oil is excellent. Otherwise, QS, Valvoline, or PZ, any 10w30 synthetic.
this grade of oil is just more shear stable, and a synthetic 10w30 has the cold properties of a conventional 5w30, so you have it all covered.