I've done it while racing downwind in 18-25 kt winds. Having never done it before, I was apprehensive about raising the twin jibs in that much wind, but we sailed downwind all night, and found that the boat was very stable, and our ability to control the boat was never in doubt. The boat did a lot of surfing that night! By comparison, we saw a number of spinnakers shredded by the wind, but the much stronger sailcloth of the twin jibs was never close to being overstressed.
In the strongest winds, I doubt that a spinnaker would have been significantly faster, but a spinnaker would have been harder to control in that much wind. As the wind eased into the 18 kt range, I think the spinnaker would have been faster.
Last edited by Sailormon6; 03-25-2009 at 08:14 AM.