We like Bosca spumante, and have searched for years for a stopper to seal the bottle so that the contents could be enjoyed over a number of days. In our experience, Bosca spumante has a similar bottle-opening to most bottles of spumante, sparkling wine, and champagne; thus, a stopper labeled "champagne" could be used on most of the aforementioned bottles.We've been using the Winco Champagne Bottle Stopper for about 5 months, now, and it works wonderfully. The operation is simple and results in a nice, tight seal on the spumante bottle. When the bottle is re-opened, we consistently hear the hiss of gas being released, and the wine still bubbles and fizzes as it is poured. Typically, the bottle is resealed with the Winco 1 or 2 times over the course of a few days, and the wine is still bubbly and enjoyable. I've left a bottle refrigerated and sealed with the Winco for up to a week, and still heard the hiss when the Winco was removed (the spumante was bubbly, but not as much so as when it is enjoyed within a couple of days of opening). Some of the negative comments others have left regarding the Winco seemed to indicate that it may have a tendency to loosen and pop-off of the bottle. We have not experienced that, nor has our stopper's grips weakened. However, even if the grips did weaken, the stopper would work equally as well if one simply applied it to the bottle and then secured the arms with a rubberband or the like. In other words, the stopper would not be a complete loss even if it didn't work exactly as it was intended. The other two stoppers - Cilio and Metrokane Velvet - are virtually useless once they break, as there is no way to really salvage them and use them in an alternative manner.Cilio Champagne Sealer has also worked well for us. Its operation is simple, and it provides a decent seal with consistently decent results. However, if I leave the Cilio on a bottle of spumante for more than a couple of days, it does seem to leak a little. In other words, it provides a good seal for 1 or 2 days, but then the seal starts to weaken. Granted, sparkling wines weren't meant to be kept at length, anyway, but...our lives get busy. As with the Metrokane Velvet, once the Cilio breaks (or no longer functions satisfactorily), it will be a complete loss, as there doesn't appear to be any way to salvage it to use in a rudimentary way. We haven't had cause to replace it or discard it, since we primarily use the Winco stopper, so I can't really comment on its longevity. We've owned it for 5 months, and have used it 3 or 4 times.When they function properly, Metrokane Velvet Champagne and Wine Sealers form the tightest fit on the bottle and best preserve the gas/bubbles in the spumante. However, they are very fragile. We've owned numerous Metrokane Velvet stoppers, and no matter how gentle we were with them, they only lasted long enough to seal 5 or 6 bottles. Eventually, they just turn and turn, and the stopper no longer seals the bottle. I've read much helpful advice from other Metrokane owners who were able to repair their stoppers, but ours were always hopelessly irreparable.