This is a bit late, but . . .
I recently got an RM20 to feed my Bryston 4B3 and was surprised at the improvement to the sound. More 3D, more relaxing, more consistent from one listening session to another, and (most important to me) some occasional harshness I've been trying to eliminate for years is gone.
I previously tried a Shunyata Denali 6000 ver 2 in this circuit, and I preferred the RM20.
I have a Furman IT Reference 15i used for my source components. When I ran a long AWG12 extension cord from the Furman's high-current outlet to the 4B3, I didn't hear a change from plugging the amp straight into the wall. So with that limited comparison, the RM20 was superior in my system in this application.
All the gear is powered by a dedicated 25-amp circuit terminated in the audio room with Hubbell hospital-grade outlets. Power cords are stock.