For those of you using the Marsupial bino harness system... which size are you using for 10X42's? The web site say's to get a size small but I've seen some discussion on here where guy's are saying a medium? I'm guessing either would work, just wondering which size would be best and why? I'm leaning towards a small as I'd like the harness to be as small as possible. Don't like a large chest pack.