Kim! You are an excellent pupil. You got it spot on.
I'll add that they will last longer since the material isn't stretchy or collapsible.
If I were brave enough to have my boobs analyzed by strangers on the internet, I would post a picture of me wearing a top with a seamed bra, seamless bra, and contour bra. The difference is quite striking. I look about 2 sizes bigger in a contour bra, and much wider and heavier in a seamless. If you are less well endowed, looking bigger might actually be desirable, and smaller bustlines (C cup or less) don't need as much support, so a contour bra is fine.