That is my experience with comcast dns too. Although, I have had some issues with google dns too on a rare occasion where I had to change back to something els

That is my experience with comcast dns too. Although, I have had some issues with google dns too on a rare occasion where I had to change back to something else (comcast or opendns) for a short while until google dns worked again. They never hijacked anything, but it just stopped working for a brief period.