Go for it. Although I've never used the Mazda 0W-20, you will see a lot of positive reviews of it here. I started with M1 in my '13 Outback, which has the same engine, and switched to PP when I got a good rebate deal. I'm very happy with the PP. Engine starts easy in cold, and runs very quiet.
Originally Posted By: ColdCanuk
Watch for oil consumption.............
Notorious oil eaters, anything under 1 quart per 2000 miles is normal for Subaru.........look at the owners manual, carry extra oil.
Don't concern yourself greatly with this. This is way over exaggerated. While it does happen, it is fairly uncommon. I have almost 19,000 miles on mine, and have not needed to add any oil between the 7,500 mile OCI. On the Outback forum that I visit, most of us report no issues. Carry extra oil? This is scare tactics.