When you use a shoulder holster, doesn't it get in your way when you hike and your arms are swinging? I think a chest holder would work well for hunting but I want my binoculars on my chest too fo easy access. I'm sure you are or were concerned about surface wear and this question comes up very often. What holsters provide the least wear on bluing?
I have maybe 100 holsters, about every duty rig ever, most of the shoulder holsters, top brands and el cheapo, leather, nylon and all of the ninja plastic holsters.
I have carried in harms way many times and I have carried in church as well. I was armed when I was married, both times, and my best man was armed, both times. The two of us graduated from a major University armed. I carried for 2 branches of the service, 4 different LEO jobs, etc. I say all that to say this.
Nobody can tell you what fits you with a particular gun, your body makes a bid difference.
You asked about should carry. I carried both 1911s and wheel guns in shoulder rigs, the Jackazz Rig now know as the Miami Classis is still the best. My used ones are going to $200-$250 on line. But several companies have copied them well and you should not pay over about $100. Also, in that style it is critical that you get the leather with the swede straps, the are comfortable. As far as vertical carry, I have Bianci and Safariland on others. Pay for the name on the vertical carry rigs. They save you when you carry a heavy gun like my Ruger Redhawk of SW model 29, when you get the big wheel guns they do not work well on the belt, unless you wear suspenders.
You asked about hiking. No they do not restrict you at all, in fact they balance you. You just put ammo on one side of your body or shoulder rig to make the weight about even. You back pack can help with that. In my protective service jobs, we often had to run to keep up or get ahead of the important official we were there to protect. If you have a big gun on the belt, you have to hold it down if you run, in the should rig it should be tie down and not an issue, it will not flop around like an OWB rig.
When you run with an IWB holster, you will have problems, even the best swede is going to sweat and rub every time you take a stride.
Your scenario is when the SHTF, that calls for concealment 100% of the time. Does not mean a concealed holster, just the gun out of sight. If the bad guys are coming to steal your food or ammo a gun showing is just like the point man in the military, you shoot that guy as soon as convenient, maybe not at first sight, but when they see the gun, you are tagged and will be killed first. Just think about it, if your family is starving and you might want to steal a chicken down the way and a guy walks out with a gun showing, you have few choices, offer to buy the chicken, or try to explain why your are there, and it is the SHTF already, so everybody is a likely bad guy, but especially the guy showing a gun.
Summer means a big loose shirt of some kind. Or a small pistol in the pocket or maybe the IWB AND a big gun close, close means 10-20, not 10 20 yards because people will walk up to your yard also. The bigger pistol must be close and long gun not far away. In my mind survival is more about tactics and planning than guns. You cannot have too much ammo and guns, and you can sell of trade them, and if yours are stolen, you have more hidden away, right? Gotta have a fall back plan.
Back to carry rigs. I have Glocks and other 9mms and lots of plastic guns. You can put them in the Kydex or other plastic, they will all scratch, but who cares if your Glock scratches. If you put stainless steel revolvers or pistols like 1911s in them they will scratch. I have nice 1911s, and I have a couple that are purely for combat with man or animal, I put them in Kydex, the Fobus brand and all of those. My nice 38 super I would never put in any Kydex or other plastic holster, unless it was my last gun. No finish made is totally safe from them.
Leather and Nylon will keep a nice gun looking nice. Leather and nylon is quiet. Nobody sneaking around behind the FEBA is wearing a plastic holster, too noisy. Same thing hunting, I will not wear them. If you do, get the minimalist you can find, like that tiny belt slide for the Glocks, they work fine.
Tomorrow I leave to go deer hunting. I normally carry a tiny 9mm in the pocket, it is black powder and I will be walking out in the dark. I have a 2.5 inch Model 66, SW, that I mounted a set of laser grips one, it will be carried in a leather holster on the hip, witht180 grain bullets in it. They have seen 2 cougars on the place, coyotes are everywhere.
In gun season, I expect I will take a 44 or 45 loaded with Deer/Bear bullets in case I get a close mule deer or white tail. I have carried the big guns on the hip, with suspenders of course. This time, a vertical leather shoulder rig will be n order. I have carried the SW 44 many times in it, you forget it is even there, even though it weighs 3 pounds. No one ever sees my hunting guns because I wear camo and a leave suit when I hunt, ever with orange on, the leaf suit kills the outline.
Just my experience. When I started carrying for a living I was thin and muscular, 31 wait and 48 chest, now it is about the opposite, LOL The shoulder rigs work for all body sizes, but you must adjust them for the perfect fit, many people do not and then complain. Also, the shoulder rigs are the quickest method for things like a car jacking, the gun is already at your left window. Another thought is what you drive, in my truck or jeep or 4x4 or horse, the shoulder rig works great. A strong side carry is often a problem with seat belts and other gear on a horse. Also, if you carry a long gun on the should with a sling, you do not want to carry on the same side, I have had the sling catch on a gun but more than once, dumb thing, I learned.
Last comment. You can buy a belt slide that will fit, everything, at least one small and one large will do so. I find them great, they will fit my 1911, all my Glocks, my K and L and N frame revolvers, just stick the gun in and go. You should buy one just for those days when you are in an out and must leave the gun, like going into a Post Office which is always a crime with a gun these days.
Anyway, let us know what you decide. My last tip, price has no relation to function. The cheapest nylon holster out there may be perfect for some guns in some situations. I have an IWM nylon, Uncle Mikes, I think that was about $10 that I use for my Glock, more than the 100 or so that fill my two holster boxes. FWIW