Rogue RP-7 vs. New RP-9 - What's the Difference?

I just got an RP-7 recently and I went to their site to look up the manual as I was setting it up and I see they now have an upgraded RP-9 model with different tubes (Russian 6H30P vs 12AU7 in the 7).  I can't seem to make out any other differences.

I thought this might warrant a discussion from those who know more than I do. Thoughts?