I just use a couple prisoners in my camp at all times as a labor force. They have zero percent escape chance. It was pretty hard to figure out at first, but you have to have a person assigned to the watch tower, the prisoners must stay injured, and you have to have them surrounded by your companions. The way you surround them is by making sure that when you assign a companion to a nearby working area, you have to move them around until that little added square that designates their resting spot is right next to the resting spot of the prisoner. I didn't realize that the physical position of the characters in their work zones doesn't matter, it's the little added square that designates where they will rest next to their work zone.
It depends: The difference is really that: Adaptive let's you gain level appropriate loot relatively easy (but you can also do that via smithing). Whilst fixed world will test you with getting the zones in the right order (which is more akin to older roleplaying games), therefore you have outdated loot from time to time (which you can again circumvent with the brotherhood and upgrading the level of the gear). TL:DR: Not that much of an impact as you might think.
I recommend the region locked difficulty if you fancy power fantasy. If you go back to previous areas that you cleared, you can enjoy being OP. Also, you can always create a new save/playthrough for the adaptive world. I'm currently enjoying extreme difficulty with the ironman setting in an adaptive world. brutal!
