Well, I'm on the side of it being a necessity
Bought our Wonder used. Put a macerator on before our first trip. I had previous experience with the stinky slinky when we rented an RV years ago.
The macerator makes dumping a lot cleaner and as far as the time spent, I think it is faster. One doesn't have to get out the large hose, hook it all up, dump, potentially get our a black water hose and connect it to rinse out the stinky slinky, then put it all away. I pull out the macerator hose (that is always connected), REMOVE THE SMALL CAP, put it in the sewer hole, open the black tank, turn on the pump and when that is empty, I close the black tank, open the grey tank and finish pumping. Then remove the hose from the sewer, put the small cap back on and stuff it back into the compartment.
It also allows you to dump uphill. We have a sewer cleanout on the side of our house. I added an elbow to turn it upwards and used the existing cleanout cap on the elbow. This cleanout is on the house wall inside a built up flower bed that rises about 15 or so inches. So with the macerator, I can empty at home as well as do all of the vigorous cleaning, winterizing, etc.