Pro, the horn is always with the bag if you have a bag for every gun.
Con, the horn isn't available to carry without the bag, or with another bag.
Sorry, I don't have photos of my set up... but I don't have a shooting bag for every gun. I'd be broke on stuff to put in them alone.
I'm right handed I shoot rifles and smoothbores of various sizes.
On my Right, I carry a possibles bag (don't shoot me, it is indeed a possibles/tool bag not a shooting bag) with my horn....separate since I have different sized horns with different tips to use. If needed, this side carries a haversack with lunch/dinner.
In that bag, I carry the basics of jags for the guns I shoot, screwdriver, knapping hammer, a couple extra flints and flint leathers, thread adapters, breech brush and scrapers etc. The otherwise loose tools are in a flat leather pouch with a slot for each tool. It folds in half and binds with a thong. (sewing kits are called Hussif, or house wife. I call this kit a housfrau-honey)
On my Left, I carry my shooting bag. It generally has the ball, patches and an extra jag for the gun in question. eg for my 45, 50, 54's, the appropriate patching, ball and a couple flints. For my larger smoothbores. I carry ball, but also the correct cards and wads with a small bag of shot. (enough for 10 loads) I also always carry a canteen on that side.
This is part of my collection I was cleaning/yearly maintenance on... excuse the rust.. that's why I was working on them. It was a wet week in camp and the tent got flooded. Served me right, my firelocks normally have their own cot to rest on, not the ground. Was teaching and is why so many.
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