Bandoliers seem like a good idea but nylon ones for shotgun shells don't work very well.
For upland hunting, I use a strap vest with no elastic on it but integrate a shotshell belt with it. I put 2 to 5 shells in the 25 shell loops at a time. That helps me do one or two quick reloads before fishing around in the pockets but pockets hold shells MUCH more securely. The weight is spread out over shoulders and waist better and it is less unwieldy.
This config comes after 30 years of walking fields and dropping shells occasionally!
For home defense, a buttstock 5 shell holder works fine. You don't need 50 rounds for home defense and slings get really annoying fast.