I might use both ... I have the RC Boost and love what it does to the front end of my signal ... especially at live volumes. I understand the AC is a bit more colored but not a lot ... maybe a Vox-ish tone. I might like to use them both as options on the front end. Seeing that I'm pretty satisifed with the RC, what can anyone tell me about the AC? What can I expect? OK to directly compare to the RC since I have one ... will help make some sense of it all.