Rolling tubes can make a significant difference. Before I upgraded to the RP9, I had the RP7 and the Telefuken tubes were more articulate, more dimensional, wider soundstage and better base. They were not "cool" or solid state sounding, but not syrupy warm either. Better than the default tubes. Mark at Rogue suggested I make the switch and he was, as usual, right "on the money."
The RP9 is built around the Russian 6J30P tubes and does not as such lend itself to much tube rolling, although there are a couple brands of 6H30P tubes. Thus far, the default tubes are excellent.