M1104 is the correct filter
I just bought Mobil 1 0W-20 oil, and they sold me the M1108 filter for my non-turbo model Forester. I opened the hood and saw the size difference so I called Champ Oil Filter (manufacturer of Mobil 1 filters) 1-800-882-0890, and they confirmed it should be the M1104 filter for the non-turbo model. I know their website gives you two different answers based on how you search out the filter for your vehicle, but I was told the M1108 (still correct for older engines and 2011 turbo) was a mistake that is being updated in their system to now reflect the M1104 for the newer designed engine. I was told, however, the M1108 will still work in the 2011 non-turbo, but the better choice would be the M1104.