I have an Espar Airtronic 4 w/ 3 outlets. It's great! Install is simple. Of course you have to run the 3" flex ducts and the exhaust
thru the hull
. But this is not difficult for a cruising sailor. You have to connect the heater
to your diesel tank using a small metering pump
. The rest is just plug
made up cables
from the t stat to the heater and fuel pump
The heat is dry, the heater is quiet and comes up quickly. No complaints whatsoever. You can install it yourself.