Thanks for providing the link for this very insightful article. Typical high level Thomas Mayer detailed and educational writing. I owned the original first production run of the Elroy 300b tubes. I had 3 pair fail in my SET mono blocks over about a 7 month period. Excellent sound but utterly unreliable.
I'm so happy to know that Thomas Mayer has thoroughly revamped the tube and solved the issues. Congratulations to him for his efforts and continued success.
Charles