I found the "Azimuth" fluxgate compass to be superb. Initially designed for military use (I believe) and very rugged. I wish I had room to fit one on my new boat!
Of course, there is always a case for a solely magnetic compass, in addition.
I was told that the Plastimo 105 wouldn't fit on Aries IV, so I had the smaller version. Completely useless at the moment! 30 degrees out on some headings. I need to establish whether it is sticking or just needs professionally swinging and adjustment for local magnetic fields.
It probably doesn't have a great deal of chance, being surrounded by quite a bit of electronic kit.