I later heard from Blue Sky, and they offered me a new unit with what they hoped would have improved noise characteristics. They were right! I can now recommend the unit for marine applications without reservation. From my email back to them:
"I received the new unit on about the 2nd, and installed it a day or two later. The reduction in noise was dramatic. I simply swapped out the boosters, leaving the metal enclosure in place, and leaving the ferrite suppressors on all the wires leading into and out of the enclosure. The noise is gone on Channel 16 , and I have not noticed it on any other channel I normally use. I even was able to take my handheld radio and put its antenna against the faceplate with no interference generated on 16. You guys have a winner."
Rating: