I bought 3 Zephyr tips when they were first launched, to give them a spin around the block. One size 6 and one size 7 tip pulled out of the socket. I called KP and I had entire new sets in my hands within the week. The new ones are fine and dandy.
I think anything newly launched has some glitches to iron out, for example, the type of glue. Even Crystal Palace bamboo circs had issues with the glue that holds the wood needle inside the socket.
But they got it resolved quickly, and all is well.
Give KP another chance to make it right for you! The Zephyr's really do perform so nicely, and the price is really incredible! Don't be discouraged! Your replacements will prolly never have a problem...but even if so...don't give up. KP will make it right by you!
Big hugs from us all!
We've all been there!