Stephen:
We installed the Marine Air 16,000 BTU unit on our IP 35 in 2002. It has worked well from Maine to the Caribbean. We spent 10 years in the Chesapeake Bay and needed it in the hot summers. Our install photos from back there are here:
fhayden.com/rockhallfleet/islandspirit/air_conditioning.htm
One our IP 27, CINNAMON we installed a 10,000 BTU unit under the vee berth and it did OK for that boat.
You can see photos here
fhayden.com/cinnamon/
AC and heat really make the boat great because when it is hot, we would simply dock and plug in and enjoy. THen in the fall, it would extend our cruising.
This past winter, and as in most winters cruising Bahamas and Caribbean, we never dock, so the AC is not used. We do not have a gen set, plus when cruising you really don't need AC/heat we find. I will say, AC was the first thing we installed on our IP 35 when we bought her.
Hayden