The free Guinness at the factory WAS god awful. That's what you happens when all that matters is a great view, cute girls working at the bar and tourism. Anywhere else in Ireland the Guinness was heaven.
We ended up with some of these. We used them on accident. Each bottle with that cap was flat some had mold. Beer from the same batch with normal caps was just fine. I think the cork caps are for wine...but its just a hunch.