This pedal absolutely rips, and I also discovered, aside from using the gain, and getting that edgy vintage Supro Combo amp sound(Think Led Zepplin / Whole Lotta Love etc) which it was essentially based off the Supro Jimmy Page used in the studio, but I discovered this thing works sooo great as an OD/Clean Boost, and the cool thing is, it works well, because it has a massive amount of output, but, even with the gain at minimum basically, the box tone of the JFets, and how they are biased just always gives it a bit of an edge, and slight sweetening/saturation to the high end, and sort of thickens up the midrange in a cool way. It reminds me a lot of using a Bluestripe 1176 without the compression. It was pretty awesome that none of my other OD/Clean Boost, or Dist pedals used as Clean Boosts can do what this does. The other fun thing is the switch, and both kinda affect the tone differently as well.
I used it to Boost my Dual Rec, and JCM 800, and it was so sweet, but love it into a cleaner amp setting too.
Unfortunately need to sell due to some hard times, but will be buying one again at some point.