I think the answer lies in what type of hunting you are doing. When I am chasing hogs I might literally walk ten miles a day, crawling through laurel thickets. Also, I wear a large backpack while hunting. A shoulder holster (bandolier holster) will not work with my backpack. For me there is no choice but to use a sling.
However, if you rode a 4-wheeler to within a few hundred yards of your stand then a holster would certainly be a good option. In other words, the more you have to walk, the less attractive that a holster is to me.
I can email some pics of my setup to you if you are interested
Hope this helps....
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