2010 Hyundai Elantra, at 102,205 miles. Using a Motorcraft filter, and a mix of weights (using what I had on hand), 1 qt 0w-20, 1 qt 20w-50, 2 qts 5w-20, for an approximate average close to 10w-30 (or 7.5w-27.5 if the bottled weights are exact). Brands used: Valvoline, Supertech, and two quarts O'reilly store brand.
ATF drain and fill, 3 qts of Valvoline Maxlife, compatible with the SPIII requirement.
This vehicle was purchased used, at about 70,000 miles. Prior to now, I'd always use 20w-50, with the logic that thicker oil would be superior in my hot climate. Now, I'll follow the manufacturer's recommendation of 5w-20, 5w-30, or 10w-30, given what I have learned since then.