Originally Posted By: tig1
Both are quality oils but the base stocks will be differant. All M1 oils are well know for long OCIs.
I've been using M-1 0w20 for several years now, and have been very satisfied with the results. My Focus runs very quite and smooth. I run my M-1 for a 8000 +/- OCI.
I have never used Castrol Edge, so I have no opinion.
As others have said, flip a coin. IMO, both are quality products, and your vehicle really won't know the difference.
Also agree that you should compare M-1 EP to Castro EDGE w/ Titanium.....and use a 5w30.