I am looking at air conditioning my boat, the summer here are very hot and humid many 100 plus days I sort of like the Coleman SeaMach http://www.pplmotorhomes.com/parts/rv-air-conditioners/marine-air-conditioners-info.pdf as a permanent installation 1300 BTU with a heat strip for winter., for about the same price as a carry on from West Marine. My concern is this unit is a roof mount @ 99 lbs. What will this do to my center of gravity and boat handling? I can already see a visibility problem while motoring. What other effect will the extra 100 lbs have?