I think most metal caps have a plastic (perhaps silicone?) insert to seal the bottle top.
Regarding cork, I’m with the “if it ain't broke don’t fix it” crowd. If there is a demonstrably better solution that costs the same or less, it would be in wide use. There doesn’t seem to be one.
Cork in wine bottles deteriorates and crumbles, potentially ruining the wine. That is what is behind the movement toward screw tops. But on a sax neck, cork works just fine.
Regarding cork, I’m with the “if it ain't broke don’t fix it” crowd. If there is a demonstrably better solution that costs the same or less, it would be in wide use. There doesn’t seem to be one.
Cork in wine bottles deteriorates and crumbles, potentially ruining the wine. That is what is behind the movement toward screw tops. But on a sax neck, cork works just fine.

