I started using MC blend (5W-20 and 5W-30) in two different cars about three months ago. Previously I've used M1, Valvoline & Castrol synthetics... for many, many years.
I moved to MC blend for several reasons. First, it has an excellent reputation for protection; it seems to be an 'ideal' oil for use in a hybrid engine; its inexpensive and available.
Previously, I did not understand the Ford oil qualifications. I thought they were more of a marketing tool than a legitimate test procedure and I disregarded them when selecting a product. Now, thanks to some help from BITOGers, I know better. I've no qualms about using the MC products (or its ConocoPhillips siblings) in any engine.
My 'real world' use experience is limited at this point. About 1000 miles in the Sienna van and perhaps 700 in the Cammy hybrid. First, nothing has blown up! Second, both engines appear to be quieter during all operating modes. The Sienna does appear to be getting very slightly higher mpg per tank ... same with the hybrid. With the Sienna.. using the 'rule of thumb' instant mpg display, it appears that its getting quite a bit more mpg in the instant mode. Which may explain the slightly higher average mpg. Not that mpg is all that important as a reference point, but perhaps it does say something about lower friction in the system?
Cheers!