Why GPS compass for 500 GT vessels only

I would recommend that any vessel under 500 GRT operating solely in the Pacific Islands use a GPS compass instead of a gyro because of the difficulty in getting the gyro serviced.

C-Nav 3050’s on most of the ones I’ve been on.

I am very satisfied with the routine use of Satellite Compasses. They should be required on most commercial vessels. A gyro should also be required on larger vessels. No reason not to have both of them, plus a good magnetic compass.