It has been a while since we have had a boat, but we are looking to get another one. My wife and I really like the look of the 390 Motor Yacht, but I have read that it burns a lot of fuel. We would like to be comfortable, but don't really care about going fast. If I were to run at hull speed using the diesel engines, what type of gph/mpg would I be getting? Would I be causing problems with the engines to run them slower than they are really designed to be run? Most of the time there would be at least 3 of us staying on the boat for weekends/trips. I like having the 2 different sleeping areas and not having to convert a sleeping area every night. Thanks in addvance for your assistance.