I use the Dodd with NOS Amperex 7308's. They're not cheap, but boy do they sound fantastic. I never even installed the JJ's, so I can't comment in regard to break-in with those tubes. In my experience, the changes of this pre during breakin were not significant. My guess is that at 50 hrs. you pretty much know the character of the pre with those tubes. The Sixmoons review of the Dodd with stock tubes is pretty much in line with your assessment. I agree with Mrjstark that Mullards would be a good choice if you're seeking more warmth. The Amperex are ever so slightly on the warm side of neutral, but maintain a wonderful clarity.
