I found the Garmin Fusion system to be one that tried to do too much and ended up not doing anything very well (including the GPS function). The switching of the cameras is very slow (using the triggers). It's placement in the dash is at a poor angle and too far from your field of view while driving. As mentioned, if you don't keep the firmware updated it can cause problems. Mine started making an occasional chiming sound like a seat belt warning. It also was very difficult to pair it with a phone and have it work when the display was connected to the dash. After getting a special pairing document from Garmin I finally got it to work. It tried to route me over 100 miles out of the way in Oregon until the map data base was updated and this was on Hwy 101. Although the GPS isn't too hard to use, it not nearly as intuitive as others I've owned.
That said, I bought a new camera system that is vastly better and mounted the large monitor just to the right of the driver's overhead cubby hole. You can route the one power/camera feed cable through the cubby hole and down the pillar through the firewall and into the engine compartment. The long cable that came with it is just long enough for a 35MB. I put the second camera just under the front license plate and didn't use the sideview cameras. This system is a true bargain. I previously had a RearView Safety system, which was pretty good, but this is much better. https://www.amazon.com/dp/B0B4D9PNFZ...t_details&th=1
I still have the original backup and side view cameras feeding into the Garmin system. I prefer mirrors to the sideview cameras, but the backup cam is now looking at the hitch so that is useful.