We have been FT in a class A (DP pulling a 24' enclosed trailer) and now in a 44' fiver. As a full timer there are differences IMHO.
First of all the maintenance costs between a class A diesel pusher and a class A gasser are different. Most class A gas coaches are on a regular spring suspension with simple components plus the engine is simple for almost anyone to service, even simple for most to service themselves. On the other hand modern diesel engines are not easily serviced and your annual maintenance will run between $800 and $1,500 per year. This isn't counting averaging in for battery replacement and tire replacement every 6 or 7 years.
Insurance costs were about the same for us. With the DP we also hauled around a car and motorcycle. With the fiver (toy hauler) we have to insure it plus the F350 and motorcycle. The biggest difference, especially in 2021, is the fact that we are getting over 40% better fuel diesel fuel economy pulling the fiver as compared to what we were getting driving the DP. That adds up in a 12 month period.
Next thing to consider is breakdowns on the road. As a full timer you can't simply have your RV towed somewhere and then go home to wait for it to be repaired. Your RV is your home and it contains all of your possessions. If you are in a large class A and have a flat tire for example chances are you will be waiting on the side of the road for hours until a service truck can get to you and change it. If you are pulling a fiver then in most cases you can change it out yourself. If you experience a mechanical breakdown and have to be towed your class A sits in the shop while you sit in a motel with a rental car. if you are in a fiver then at least you can have your "home" towed to a campground while you are waiting for the repairs on your truck.
As far as the actual traveling during the day, we like the fiver just as much as the class A's we have owned. The DW can't get up and move around while we are going down the road, but we the mega cab F350 we have about everything within reach right in the back seat anyway. We always stop about every 90 minutes no matter what we are driving so that didn't change.