I always used Motorcraft 5w-20 Semi synthetic in my '02 V6...ran it hard (changed it every 3K miles)...even at 65K miles when I traded it in for the '06 GT the V6 ran like a champ and never burnt a drop of oil. I've just changed the oil in my '06 at 650 miles (old habits die hard...to get rid of any shavings from a new engine) and I plan on using Motorcraft's 5w-20 Semi-Synthetic for the life of this car. I believe its good oil. I also use Motorcraft's 820S filter.
(My '01 Vette uses Mobil 1 5w-30 full synthetic...came from the factory that way...very pleased with Mobil 1, too).