Hi Richard: In-the-masts furlers are considered easier to use than in-boom, which require close monitoring of boom angles when furling and unfurling. Neither system is trouble-free. In-the-boom is much more efficient, with a much lower center of gravity and less windage. But honestly, I am not a fan of either, as they are both heavy, costly, and subject to operator error. For ocean crossings, I think a conventional system, with proper full-length battens and slab reefing is better. The in-boom/mast systems are fine, though, for coastal work. There is a much more detailed discussion, and lots of photos, in our Offshore Cruising Encyclopedia. Steve