Bayreuth, Thanks for pointing these out. I have heard nothing about them, but I just bought one to give it a try. Got one for under 40 shipped, which is less than half the current price of the create synergy tubes.
I really love the synergy tube, but its an inexpensive experiment. I'd love a tube with the dynamics and low noise of the synergy with the classic tube sound of the old mallards. That is asking a lot, but ---- one can always hope.
By the way, love your user name!