I went with the Furuno NavPilot 300 also after a lot of comparison shopping at boat shows and on other people's boats. All of the other brands look like toys when compared with Furuno. The installation was straightforward, but the setup and calibration instructions were confusing. I got some misinformation at a boat show that the unit would not require a heading sensor if used with GPS. This was wrong, but I had already started the setup procedure and had trouble backing out and continuing the setup after I got a heading sensor. I needed to go to Furuno customer service for help and they were excellent. They answered the phone and I got to speak with someone who seemed to be an engineer. He solved my problem in no time.
I don't agree with recommendations about getting an AP of the same brand as your MFD. I was headed in that direction since the Navico units have a neat feature that automatically lets their AP start to navigate as soon as you set up a destination waypoint on the screen. I thought this was a cool feature when I saw it on a friend's boat, but it turns out to not be a big deal. All of the different brands of APs work through NMEA 2000 and are recognized by any modern MFD. All I have to do with my Furuno is to turn the unit on after setting up a navigation target on the MFD and press the standby button twice and it follows the path.
The Furuno has a couple of features that the other brands lack. It has a handheld remote in addition to the normal display screen that lets you dodge obstacles or steer from anywhere in the boat. It also will set a path to a destination simply by pointing the remote at a target and pressing a button. Finally, it has something called Sabiki Mode that will hold the boat at a fixed position with the engine running in reverse. Sort of like a virtual anchor. This feature doesn't work as well as I had hoped on my single-engine boat. It may work better on a larger hull with dual engines.
The only thing I don't like about the Furuno is that the heading sensor is not waterproof and needs to be mounted in a protected area. Not a big deal, but it cuts down on your installation options.
My unit has worked flawlessly for over a year now.