I'd say that the colorful ones will definitely draw the eye: our eyes are instinctively-drawn to shiny and colorful things: that's why the black's the traditional 'pro' color,anyway. I'd keep it to subdued, dark, or earth-tones, if you don't want to draw attention from your subjects. It's not really about 'hiding,' just not being a distraction.
That navy blue doesn't look too bad, though, if you wanted to be a little different without waving anything too flashy. There's olive and sand colored ones, too, but those might just look too military for comfort.
There might be some advantage to the more-toylike colors making the gear look cheap and whimsical, in some places, though.