Tube rolling with CAT preamps?

I recently replaced the stock tubes in my CAT sig with NOS GE smooth plates and rocket tubes in the phono stage. WOW what a big difference. Far superior dynamics and waaay smoother across the spectrum plus a much larger and deeper soundstage. Has anyone else had a similar experience rolling their own into CAT pre-amps?
When I had my SLI MKII I used VAC tubes. Great folks, worked through all my questions and the result was A+.
Bozo, what kind of VAC tubes were they? Do you still own the CAT, or if not what did you replace it with, why?