Has anyone of you ever used or know someone who has used one of those bow blinds. They are camo umbrellas that mount in your sabilizer hole and have a hole in 'em to see/shoot through. They look like a pretty neat idea to conseal your draw. Anyone? They claim it's really light. It only measures like 36". They claim it actual works like a sabilizer and reduced shock/vibration. Just don't know any one who has used one. Any one know who makes it? Or where to get/look at one?