Re: Full or fin keel?
There are also cut away and modified keels. Much of the choice depends on your sailing preferences: fast vs comfortable (sea kindly); deep water ocean cruising (deeper keel) vs Bahamas bank or wanting to pull into shallow harbors (shoal keel); etc. As mentioned above, having the rudder be shorter than the keel and protected (hung or skeg) is import for cruising. We have a heavy boat with a 5.5’ draft. She’s not fast but she’s comfortable (aka civilized) and sea worthy. With the 5.5’ draft there are a number of hurricane holes here in the Bahamas that I can not get into and harbors that I have to wait for high tide to enter. I’m ok with these trade offs.
As all the sailboat cruising and boat buying books would say, there are always trade-off when aquiring a boat.
Mariner 39 (NH built, cruising version)