Apart from one mishap, the screwtop thing has worked well for me. Have just returned from France, where increasingly French wines that previously wouldn't have been seen dead under a screwtop now have one instead of cork. I predict that within five years cork will have disappeared from Europe, as it has in Australia, New Zealand, and now increasingly in South America. And screwtop is so much more convenient, as others have stated.

The mishap was one where the screwtop machine had obviously malfunctioned. The shank that clamps to the neck of the bottle had not clamped, and the entire assembly was thereby able to spin on the top of the bottle, resulting in leakage and a wine that had maderised. That's the secret, it seems to me: ensuring that the shank is securely clamped to the bottle neck as well as that the top of the cap is properly pressed against the top of the neck.