W20 is default OEM for many Honda, GM, etc... engines...
There's a Japanese website, I can't remember where, with a list of cars that can use Mobil 0W20. Latio/Tiida is on that list. And Mobil 0W20 is thin indeed.
Not recommended for chiongsters. But for those of us who seldom use more than 20hp out of 109hp, it should be okay...