We have an ATN sock. Blanket the chute, pull the sock down, then the world gets a lot calmer -- even if the wind is in 20-25 knot range.

However, for specially cut asymetrical chutes with appropriately sized hardware, the roller furling seems to work. I'd be very cautious about leaving one of these up furled in a blow -- whether under way or anchor/mooring/dock situations. But they are used by some pretty sophisticated crews and on performance boats that wouldn't do so if they didn't work.

Having said that, they don't stow as easily as a sock. If you have to sleep on one down below, they aren't as comfortable either ;^))))