Myles - I replaced the V1 in my Hot Rod Deluxe as you suggested. I originally tried an Electro Harmonix 12AX7 and noted an improvment. However, on the clean channel I go from "0" to full volume at 3 or 4, then increasing levels of OD. I contacted your friends at kcanostubes.com and went w/ a Mullard 4024 (12AT7) for less gain as I am looking for a very clean sound in this channel, but I still go into OD very quickly. Could there be a taper issue with the volume pot? Also, do you know what benefits would be derived from replacing V2 and V3? I'd like to make the OD channel more useful, but I don't which tube(s) it uses to generate its gain (I'm guessing V3 is an inverter tube)?