There's extra weight aloft and greater windage, due to the
furling mechanism. They're still relatively unreliable, esp.
as compaired to jib furlers, you could have lots of trouble
furling when not directly into the wind. They have the potential
of binding if the sail isn't perfectly straight as it goes in. It's your
primary means of propulsion (well, for most people). Why mess
with it? Also, on a 35-40 foot boat? Do it manually. It's not that
hard.

"Bobsprit" wrote in message
...
For a cruising boat 35-40 feet, how much performance is lost with an
in-mast
mainsail furling system. What are the specific losses.

Thanks for any info.

RB