My 2 cents worth: I am not convinced that you need the barrier coat: 1) Your sailing season is relatively short. 2) Your water is not all that "warm." And 3) My understanding from visiting with Bob Eeg (just purchased Hull #623, my 2nd M-17) the newer vinyl ester materials are not that susceptable to water penetration. I suggest that you visit with Bob to get his take on the situation. On the other hand, how much money are we talking about here? When in doubt, I always fall back on the "ounce of prevention ..." dictum. The final answer at our houseultimately comes down to "what gives you the best night's sleep." Merry Christmas from Rockport, Texas & Southwest Harbor, Maine. Skip Langley