IMU such as the BN0080/85 as a heading sensor vs a Fluxgate compass


Have Fluxgate compasses been considered as a heading sensor?
There is a lot to be said for the low cost of IMU’s, The BN00800/85 are cheap but they have tended to drift. (I just got a new, shiny BN0085 to try out).
The marine autopilot industry has really struggled with this and they have attempted to go to IMUs only to save $$, only to get beat up by their customers when their IMUs drift over time.
It seems that the better Autpilots have compromised and they now use a Fluxgate compass for immediate correct heading direction and then use an IMU to determine rate of turn.
I’m all for saving $$, but I suspect some of you guys are auto steering tractors that cost more than my house.