Dave here is my personal opinion. I camped and traveled for several years with a hallmark pop-up slide in camper in the back of my half-ton Chevy truck, the truck was four-wheel-drive so that rig would go just about anywhere and it certainly went everywhere I wanted to go. But a big heavy slide in camper like you're talking about can be a real handful. In my opinion some of the downsides are, they're very expensive, they cost as much or more than my Arctic Fox, they require at minimum a 1 ton Dooley, and that wide truck will then become your daily driver that you will have to find wide parking spaces to put it in, when you get set up in camp and find out you're out of beer you have to either break camp and load everything back into the camper or leave the camper sitting on the ground and drive into town without it. And bare in mind some RV parks will not allow the camper to be set on the ground. Another thing that will get old really quick is having to move things to get to what you need, and the smaller your camper is the more things you will have to move to get to whatever it is you need.
As for the Arctic Fox 27 – 5L I do take it on Forest Service roads, but I try to use some common sense. It won't go places the slide in camper will go, one of Its biggest problems will be the trailer is 12'9" tall and you will find a lot of branches a lot lower than that. The factory advertises that the trailer is built for some off-road use and I take that to mean reasonable roads and not Jeep trails. When I go looking for places to boondock I do the scouting in my truck, it has four-wheel-drive but I don't boondock in places that I need it, from what I've seen so far there's really no need for me to get that far out in the sticks.
So I would say this, if you want to be comfortable and do some moderate Boondocking the Arctic Fox 27 – 5L is a well-built trailer that will give you room to move around in when you're stuck inside because it's been raining for 3 days. But if you want to get way out there where there's nobody but you, the slide in will do that a lot better than a trailer. P.S. if you decide on a slide in make sure you know the meaning of "wet bath".
Thanks for the question Dave, feel free to stop in anytime.