If you're looking at the Four Wheel Camper, then a lot of the pros and cons of normal campers don't quite apply.
I've got an All Terrain Camper and love it. At the time I bought it (2012) they were basically the same as the 4 Wheel ones but 3k cheaper. As in there was a scuffle at FWC, and some guys moved 10 miles away and started their own camper company, so they are
very similar. Since then FWC has been adding a lot of stuff and price, and ATC is kind of the same as it ever was but obviously costs more than 12 years ago
Better than a hard side camper:
Lighter
Less wind resistance so better mileage
Less wind resistance to the side so it's more stable
Lower CG. There are not many places I would take a stock Tacoma that I wouldn't take this camper
Extremely durable. Mine has been on its side and instead of exploding into a million matchsticks, I took it to the factory and they replaced all of the dented panels. That was 9 years ago.
No overhang off the back, means no trailer capacity compromise
Easy to put on. Don’t need to drive under it perfectly. Just get it on the truck bed and you can shove it into position.
Worse than a hard side camper:
No overhang off the back, means less room inside
The soft side doesn't insulate as well as a hard side. But I've been out in -15 and the heater keeps up. Both companies offer an extra layer pack that velcros in and you would want that in any weather.
Different than a hard side:
Less room means less stuff.
Mine has no water heater, shower, microwave, air conditioner, toilet, and I've only got the hand pump on the sink. Maybe you want that stuff, I don't.