On the subject grunt tubes: I have one, not to call them in, but to get them stopped or, if the need arises, to try to get them to turn around if they're moving away from me. One buck that I spooked stopped running away and turned around to face me when I blew an aggressive grunt. If I didn't have my grunt tube that morning, I doubt I would have killed him. On the other hand, I've had younger bucks just look at me funny before going about their business when I called at them.