Now, as I thought, Midnight Mission is pretty similar to OPI Russian Navy Suede with a shiny top coat. I wouldn't call them dead-on dupes, but they are similar enough that the average person might not want both. In sunlight, the difference is obvious- Midnight Mission is darker and more navy-colored. OPI Russian Navy Suede is lighter and more purple-y blue. Both of these pictures show two coats of MM with shiny top coat and two coats of OPI Russian Navy Suede with shiny top coat.
So, if you were looking for dead-on dupes, you're out of luck. If you have some sort of self-control (i.e. you are the opposite of me) over your polish collection, you might decide you don't need Midnight Mission if you have OPI Russian Navy Suede, or whatever.
In other news, the poll results were kind of what I figured- 55% of you (like me) are planning to pick up one or two polishes from OPI Swiss. Which ones are you leaning towards? I'm thinking about William Tell Me about OPI (I don't own LPAD), Lucertaine-ly Marvelous and Diva in Geneva.