I sat for my Masters exams last year and the sail endorsement test was by far the easiest, but it would have been difficult for someone with little or no sailing experience. I home studied, no class, and there was no requirement that any of my sea time be in sailing vessels in order to qualify to take the sail endorsement. I only got a 50 ton rating because all of my time was in smaller boats (the minimum rating given is 25 tons). By the way, home study is extremely time consuming and difficult, only about 10% pass, I'd strongly recommend taking a class. It's shocking how much of it I have forgotten already though!
SV Laurie Anne
1988 Brewer 40 Pilothouse