I have the smaller version, and I've rattled in many does early season, and bucks during the rut. Will be taking the MAG to Colorado during the elk rut, hoping to get the same results. These are easy to carry, no snag issues.
The Knight and Hale rattling device is one of the top products on the market for luring whitetails in for a lethal shot. IMO, sounds and resonates much better than rattling bags or synthetic horns. Very compact for carrying in pack although I secure mine to my pack strap so I can get to it quickly. This product absolutely works if you know the sequences of rattling/tingling.