Have you read this in-depth review of 6DJ8/6922/7308 tubes in Audio Asylum's FAQ section:
http://www.audioasylum.com/scripts/d.pl?audio/faq/joes-tubes.html
Well it doesn't answer your question directly, but will give you a broad overview of each tube's strength and weakness. I've tried most of them on my ARC LS-2B mk II, and I agree with most of Joe's assessments. My favorite is the Mullard Master Series 10M 6DJ8 which is not reviewed by Joe. This tube is very rare. I was just lucky to find one at a local electronic store. When it dies, I will be replacing it with my second and third favorites: Amperex 7308 whitle labels, and Amperex 6DJ8 orange globe lable.
FrankC
http://www.audioasylum.com/scripts/d.pl?audio/faq/joes-tubes.html
Well it doesn't answer your question directly, but will give you a broad overview of each tube's strength and weakness. I've tried most of them on my ARC LS-2B mk II, and I agree with most of Joe's assessments. My favorite is the Mullard Master Series 10M 6DJ8 which is not reviewed by Joe. This tube is very rare. I was just lucky to find one at a local electronic store. When it dies, I will be replacing it with my second and third favorites: Amperex 7308 whitle labels, and Amperex 6DJ8 orange globe lable.
FrankC