-The amp produces its rated power of 6 watts with about 5 percent distortion at two o'clock on the volume control (it is not numbered). Feedback is well controlled. The amp is very well made, with a hand-crafted circuit similar in design to a blackface Fender Champ from the mid-60’s era.
-Changing to a 6L6 power tube in the amp does nothing to increase the power or improve the tone. It sounds and performs better with a 6V6. Also, the magnet on the stock ceramic speaker makes many 6L6 tubes a very tight fit.
-There is a slight reedy quality to the tone that detracts from its warmth.
UPDATE 11/26/11: The amp is substantially louder now. Same room, amp settings, mic, and harp. I suspect the speaker got broken in during all the hard playing at Mission Amps while we were proto-typing the mods. The tweaks to the tone stack also focus more of the amps energy on the harp spectrum.