I have a very old 12 inch Stanley that I recently cleaned up. Had it half a century, and it had a few miles on it when a family friend and carpenter gave it to me, along with an old 13 oz finish hammer. I also have a starret 6 inc and 18 inch, which are new and pretty good. I find myself using the 6 inch fairly often for marking for crosscuts. Just handier. The old stanley is very accurate and reminds me of the guy who gave it to me. He died when I was about 25, and he used to take us boys camping and for two summers, I was his apprentice on finish carpentry jobs. He also built 4 of my mom's apartments, which gave me even more exposure to construction. Funny how things can bring up so many memories.
At any rate, accurate marking also requires using some kind of blade to make the mark, and it also requires "sneaking" up on the mark. And for interior parts, that's what story sticks are for. The picture is of the knife I use. It has a flat side so your mark is righ on the line of a straight edge.