I’ve tested a number of speakers in the Two Stroke but never the Red Fang 10, please report your impressions.

Here is a link to Bill Machrone’s 12A_ tube tests: http://home.comcast.net/~machrone/bjr/bjtubes.htm
Bill does very thorough testing and offers credible information.
Looks like the 12AY7 is his choice for more headroom.