i'm not sure I can answer all your "sonic" questions intelligently. I have Aerial 8 speakers and a Rogue stereo 90 with super magnum upgrade. The herron is a nice pre. i don't know that i'm setting out to upgrade or just "change" as you suggest. the thing i don't want to do is go backward. i want nice quiet, good separation, neutrality. I want a nice deep bass extension without booming. when I ask a question like this I guess it helps if a person owned one and made a move and was really happy.