NB swing-top wire bails... No good?

[nikkuchan]

I use swing-top bottles, and I collect various kinds when I find them. Some of the bottles I got had tops with non-removable gaskets, so I had to replace the whole thing. I got a pack of wire bail caps at Northern Brewer. They looked fine to me (the wire pieces looked the right length, the cap was the same size). I had only used one so far, and that beer was 100% flat (tasted good though). I'm hoping it was just this one. I will use this same cap, and another from the pack with my next brew and see if they hold up.

Does anyone have any experience with the NB wire bail caps? Have they worked for you?