Any autopilot that interfaces with your NMEA2000 backbone will work, regardless of the manufacturer.
I have a Furuno Navpilot 300 on my boat that is independent of my Simrad NSO EVO3. My neighbor has the same Simrad with a Simrad autopilot. Each has its pluses and minuses.
The Simrad autopilot interfaces with the MFD directly, so you don't need to add a separate display on your dash. You can tell it to steer to a waypoint just by touching the waypoint on the map display and telling it to go. I helped my neighbor set up his system, which was rather difficult and confusing. Simrad support was terrible. But once it was properly initialized after several attempts it worked fine.
My Furuno uses a separate 4.1" display that works independently from the MFD except that it acquires GPS information automatically from it to steer toward the waypoint. It senses when you have the MFD tracking toward a waypoint and automatically enables the navigation mode. Steering toward the waypoint only requires pressing 2 buttons, which is no big deal. The Furuno was easier to set up and Furuno support was excellent. They answer the phone and you talk to what seems to be an engineer who will walk you through the setup procedure. One big advantage of the Furuno is that it has a handheld remote that lets you operate the system from anywhere on the boat. This is very useful for dodging crab traps and other obstructions while trolling. The whole unit seems to be more robustly built than the Simrad even using metal connectors for the NMEA leads. The Furuno also has a Sabiki mode that holds your boat in a fixed position when fishing or getting bait. But I find that his only works well in calm water.
If I got a new autopilot, I would go with a satellite compass. They are worth the extra money. Both of the installations I did used the Simrad or Furuno fluxgate magnetic compass. It is challenging to locate these magnetic compasses in small boats without electromagnetic interference. In my case, I just had to live with 10 degrees of deviation on certain headings. This is not really an issue when following a GPS course, but it can be annoying if you are a perfectionist like me.
