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?
irrenarzt
I have and love the RP-5. I always thought the RP-7 was a balanced version of the RP-5 without the phono. I'm sure there was more to it than that. I'll be curious how the RP-9 compares to the RP-7 AND Rp-5.
Post removed 
I had a chance to compare an RP7 to an ARC Ref 6, then I learned a little about the difference between the 6H30 and 12au7. The former is going to have higher transconductance - there’s supporting discussion on the technical side if you search it. I did feel that the Ref 6 resolved better, however in my system the RP7 sounded smoother in the highs - but not as resolving in the highs, and more fleshed out in the lower midrange and upper bass, but lacked the low bass power of the Ref 6 - the Ref 6, like the Ref 10 is much larger and packs beefier power supplies. Perhaps the Ref 6 was more accurate, but I preferred the RP7 overall. So if Rogue keeps the smooth character of the 7 in the probably more refined 9, it should be very competitive with more expensive options, but I wouldn’t expect the low end you get from the ARC models.
Audio Research's well received Ref 10 preamplifier utilizes (8) 6H30P's. The RP9 uses four.

Rogue msrp $7500 vs ARC msrp $33,000.

Looking forward to hearing the RP9! Always a great value product.
Chassis dimensions are identical for both, but that makes sense as they mention their "award winning RP-X hardware and software platform", which indicates to my mind that they are using the same base to work off of.