I can't help it. I'm ambidextrous (or some might call it "feckless") between The Big Two.
I came to comics late in the Silver/Bronze Age transition. Mr. Fantastic and the Invisible (then) Girl were already married. The Teen Titans were all sidekicks (including Dick Grayson and Wally West). Iron Man still needed his armor to keep his heart beating. Black Canary was an interdimensional illegal immigrant. Spider-Man was in college. Martian Manhunter was a guy that used to be in the Justice League.
DC and Marvel were different animals, and fans took sides.
I never could. I loved Moon Knight and Ms Marvel every bit as much as Batman and Wonder Woman.
So, the point of this: did you have a preference? If so, why? If not, what was it you loved about each?