I am considering using a FLIR Duo R as a FPV camera using the HDMI port. Does anybody have experience with using a GoPro as a FPV and the mounting with the CG balance. The Duo is very close in size/weight, so any balancing and mounting experience will be very helpful. For now, I am using the X5 which allows for quite a bit of space between the mounting rails and the top of the X5 Gimbal mounting board.
I have a night waiver, so the combo will be helpful in maintaing vigilance in flight. Any thoughts from the community?

If the FLIR  Duo R has a HDMI out or an AV out, then it should be fine.