Quite possibly the best overdrive and/or distortion pedal I've ever heard. We tested with a Epiphone Les Paul Special with '59 style pickups that coil split, a 1986 Ibanez Pro Line with a hot bridge humbucker through a 120w Crate 1x12 and a Epiphone Valve Jr with a Celestion Ten 30 and a Princeton preamp circuit.
Both guitars, all the pickup combinations, and both amps sounded incredible when hit with this pedal. We added a Behringer Reverb Machine after the Germanium 4 Big Muff Pi and ran through the effects loop of a L.R. Baggs Venue preamp. This only improved the experience.
We could dial anything from clean boost to full on fuzzed out distortion using either the overdrive side, the distortion side, or both.
Both reviewers agree, quite possibly the best bang for the buck in distortion pedals. Any guitar/ amp combination works well and music style that needs a good boost to an all out distortion party will benefit.
Lastly, the small tube amp is 5w and has a gain circuit. We set gain and volume to about 2 and still had great tone that you could talk over in a 10' x 12' room. Great for practice/ rehearsals.