Well, I currently wear an Oxygen25 controller on a strap onstage, and although I can't speak to how "awkward" it looks (since I'm the one wearing it), we've played multiple shows with it and had people tell me that they liked that i played synth out from behind a keyboard stand and could dance around, etc (we play electronic/industrial so maybe it just works for our style of music?).
In terms of "useability" it is really great, because (since it is so short) i can just sort of "spin" it around to behind my back when i'm NOT playing it and it's not in the way at all. Like i said i can't speak for how it looks (though I GUARANTEE that the minibrute would look 100x cooler than the cheap Oxygen USB controller), but actually playing it like that is nice as long as you have the strap set to the correct length. I usually wear mine over my belt buckle so my arms are in a somewhat natural position to play keys and still tweak knobs, etc. A big part of what I use my synth for is to be the "formant" for my Vocoder (an Electrix Warp Factory), so being able to tweak while i sing and play makes for WAY more dynamic sounding vocals.
Like I said, at least it works for me! I am super excited for how much better the vocoder will sound with a real analogue synth like the Minibrute as the formant! Now they just need to ship our pre-orders ;-)