Charles, well this is a conundrum and no mistake! As you know, my point of comparison for the Elrog 300B was the Psvane T1 black glass 300B, which I also suspect may be Israel's reference tube. As you also know, I issued a rapid and emphatic endorsement of the Elrogs, with the caveat that I had no experience with the Taks, EMLs, WEs, and Sophias. One more thing you have no doubt noticed, is that sort of rapid and enthusiastic endorsement is uncharacteristic for me. I was much more reserved in issuing an endorsement of the Psvane WE 101 replicas vs the Psvane HiFis, for instance.
I have to think this is a case of some variability from tube pair to tube pair. Clearly, you and I are on the same page, but I think it is just as clear that we share Israel's values, since we both have all Coincident systems. I can't make any other sense out of this. I don't think I'm inclined to second guess Israel's ears, but I also respectfully disagree. The Elroy's are a substantial improvement, and are a great value based on cost/performance considerations.
I took no little comfort in having you validate my assessment of the Elrogs. You know what? I'm going to stay in my happy place. Barring a dependability issue with the Elrogs, I have NO desire to experiment with other 300Bs.