I built my own that is very much like the Seaview mast mount and I think that the accuracy performance on my radar was improved. A word of warning, if you mast mount, be aware that you can have a
halyard catch it and rotate 90 degrees if you are not paying attention.
It's only happened once, at night, between two islands, tacking in strong rainy
head winds and against the
current and suddenly I didn't recognize the coastline on the
screen. A quick trip to the fordeck to see where I was revealed the problem. Scary
Barry, S/V Whoosh