We've had both. From a maintenance perspective, I think the pop-up was much more work.
We had a 1999 Starcraft Venture pop-up with no bathroom and only a 10 gallon fresh water tank under the kitchen sink. It had no sewer outlets, just a connection for a garden hose. Where you put that garden hose to drain the sink was your choice. We carried a 6 gallon container to catch the water.
But that pop-up was WORK from the very beginning. Here's some examples:
We had it for 6 years, and it seemed every time we went camping, we always broke camp in the rain or in extreme wet conditions. I mean EVERY time! Mother Nature hated us ... I swear! That means putting the canvas up wet. That mean, bringing it home and opening it up again until it dried completely. And if we came home in the rain, sometimes in Indiana, it would rain for 3 or 4 days. This was always the number one task, getting the canvas dry so it would not mold and mildew when the thing was closed up.
Second was the mold and mildew. It took a LOT of work to keep the mold and mildew out. It didn't matter, if there was one drop of water anywhere inside the camper when it was folded up, and hour later there would be a mold spot right there. I cleaned canvas and washed down the insides so much, I hated the thing after a while.
Third, well, I suppose because it got washed down so much, the canvas protection also got washed away, as did the awning. So, I went through cans and cans and cans of tent sealer spray for the canvas sides and the awning over that 6 years.
Next, the canvas shrunk up in the second year of ownership and actually ripped. Under warranty, all the canvas sides were replaced at no charge to us. But it was a real pain, and the actual cost was over $3000 for replacement.
What happened next was partly my fault. The awning was held in place with rope tie downs, and one day wind caught it and flipped the whole mess over the top, The poles punched a hole through the roof. Insurance replaced the entire roof, at the tune of $4000.00 and 2 week in the shop.
We had a leaf spring break on a return trip home one year. Fortunate, we were within 10 miles of home and a towing company put it on a flat bed and took it to our house. I replaced the leave spring myself, including the holes in the floor of the camper from the damage from the tire that blew at the same time.
We also found out welding a hitch to the back end for bicycles was the worst mistake we could have made. When the bicycle carrier and bicycles were added, there was no weight on the tongue, and we had the most unbelievable fishtail experience anyone could imagine (I'm not taking sway, I mean uncontrollable fishtailing). I had to remove the bicycles.
Then, someone tried to steal the propane tank in Normal, Illinois when we were in a restaurant down town that Sunday. That was fun fixing that mess up. They din't get the tank.
It did not have a refrigerator, but came with a worthless ice box. I removed the ice box, get Starcraft to send me a color matched door that fit that space and turned it into 2 shelves. We then got an electric cooler that worked as our refrigerator for the next 6 years.
We purchased bunk fans separate, replaced the battery twice because it over charged and burned them up, we replaced tires twice over the 6 years (and the trailer had no brakes).
It did have a furnace and it worked great! But in damp, wet, cold weather, we were miserable. We did a lot of winter camper too. Snow on the ground and it was actually more pleasant at 10 degrees than 85 in all that wet!
We only paid $6000 for the pop-up brand spakin' new. I think over the 6 years another $12,000 was put into it for upkeep, maintenance and repairs. And we sold it for trade in for $4000. But when we traded, the pop-up still looked (and smelled) like it was brand new.
What was good about our Pop-Up, well.... it was our first non-tent on the ground experience. We loved the thing, just couldn't deal with all the wet, and the wife finally said, get me something dry or I'll never go camping again. Thus, our first hard sided trailer.
Now, I've had 3 travel trailers. Other than wash and wax, and washing the roof and treating it with Rubber Roof Conditioner a couple times a years, all 3 trailers combined have been less "WORK" than that 1 pop-up.