Yes, as with most gear, things have broken in nicely over the past few months. I now have the amp paired with a wonderful Smash pre-amp. This combo is more resolving than the previous combo of Sex and Foreplay.
It's amazing to me that just when you are satisfied with your system and think things can't get much better, you can still hear major improvement when you replace some key components.
I have better imaging and can hear more subtle details in the music. I have just done the Smashup upgrade and as Doc mentioned this was also a major improvement. More power and detail yet again!
I did try swapping out the Seductor's EL84 tubes from some nice vintage GE's to some new JJ's and was surprised at how good the JJ's sound. A little more mellow highs paired with a solid bottom end with no lack of detail. It's fun to roll tubes and hear the subtle tone and detail changes happening in your system.
For now I'm very satisfied with this combo and feel I'm set for many years of exploring my music collection all over again.