Just for the record, my comments were just that...............I'm not an owner but have chartered & crewed with a number a boats w/ mast furling systems.
I would never choose / buy one.
As I said before & GT/SD have stated real life problems. Having a sail jam in high winds is no picnic & BTW why do things like that always happen at the worse times.
I was out on a private Jenneau yesterday 43DS with in mast furler....the owner is a "fan" for the benefits & acknowledges that he has given up sail shape & controls to get it...............sailmakers are trying to compensate so he plans to factor that into his replacement sail.
I also have been on a Hunter 36 with it and chartered boats with it. All the negatives don't come close to outweighing the benefits. I would love to try an in-boom system............curious what the costs are.
My system of choice is a beautiful full main sail (and lighter mast) with all the bells & whistles plus a lazy jack / stack pack. Bet I can sail faster plus handle my sail easier than the in-mast guys.