Yes, they work great but...
I bought the entire four camera Vision S system with the larger display. This includes the rear, two side marker cameras and one porch camera. They were installed by the dealer who did a good job.
It is nice having the ability to see either side but I don’t use those side views very much. I leave the display set to the rear camera. My mirrors are my first place to look for side views.
When I bought the system, I thought I would be able to leave the display set to the multi-camera view where I could see all cameras at once. Not so. You can touch the screen to get all four cameras to display at once but the picture only lasts for five seconds before switching back to a single camera. Furrion says this is because the latency of the video feeds increases when viewing all four cameras such that they become “unsafe”. When viewing all cameras at once, they definitely get jerky and a little blurry.
One of the features is the display can be taken inside the trailer so that you can use the cameras as a security system with 360 visibility. But if you wire the cameras to the marker lights power line, you must turn the marker lights, including tail lights on. Most people in the campground would be especially annoyed if the bright marker lights of my trailer were blasting the darkness of the peaceful campground at night so I leave it off. I wish now I had them wired to an independent circuit so I could actually use it this way.
Hard to say if you will find this a good purchase. I am sort of in the middle. I like having them, they do look cool on the side but I could do without all the camera except the rear. That’s a must. I would say if you don’t have any other important or safety mods you have made (replace stock tires?) and you have the $850 for the system, then go ahead. If money is tight or you have other upgrades, you can do without.