Video camera on top the mast?

[Looking4Neptune]

I am looking for recommendations on putting a video camera at the top of my mast. I sail a 46 ft catamaran in the South Pacific and visibility for coral heads and when in narrow passes can be challenging. I have a B&G nav system that can take video inputs or I could run the video to an iPad at the helm.

Do you have a video camera on your mast?
How well does it work?
Is a 'fixed' cam good enough, or do I need pan and zoom?
If I get one that can pan, will it be helpful when pulling into a dock? (visibility of my aft port corner is not great from the helm)

thanks,
Pat