They all sound nice to me. Are you trying to match it to a bag? Or looking for something different. The Vernis sounds the most different to me and is what I would like to purchase. Otherwise, I'd just look at whether you have more Damier or Mono bag and decide that way.
I just bought the largest size mono cosmetic case. The reason why I went with the largest size is because the smaller ones wouldn't accommodate my makeup brushes. I actually bought the medium one first and it just wasn't big enough so I exchanged it 2 days later.