Since I am a Harry Potter fan, I'd go with this one, but you can decide whatever works for you.
I do'nt know how the cape would act when you upload transparent image, so I'm not sure about this one
and also you'd have to consider how the dimensions and resolution will affect the final look of it
so pics like this wouldn't really work great (unless you crop it and upload then)
but other than that everything would look great. It would be fun if max did an update so we can upload skins for capes just like for weapons. Without a need to buy user cape.