Having guarantee issues with KR Audio?

One of my KR Baloon tubes decided to permanently sleep in this morning, so I spoke with Israel Blume of Coincident, and it seems that not only is KR Audio not going to be supplying tubes for amps other than their own any longer; but getting them to honor their 6 month guarantee is also a problem. He cited a case where they said that the tube being returned was "not used properly". Not used properly in a Coincident amp??
The tubes I got through Coincident were purchased in December. DECEMBER! I checked the KR website, and clearly they claim to have a 6 month guarantee.
The best he could do is to offer me a replacement tube he has in stock for $300.00. I'm going to buy it, but man am I steaming.
I just wondered if there are any other KR tube users who wanted to rant.