Gnarled OD, singing distortion. This pedal does it all well, and with a simple set of 3 knobs. It responds well to boost pedals in front. A Keely Katana into it produces a rich, creamy distortion, while a Tumnus going into it gives a bit more trebly/middy honk. It is all very usable and musical - as a blues/rock guy, it suits my taste. If you were a shredder who needs a focused compressed Marshally tone, maybe it wouldn’t suit, I don’t know. I gave 4 stars for features just because there are not a lot of fancy features, not because of any deficiency.
I run it in parallel to a Catalinbread 5f6 bassman... I thought that would be by only always on foundation pedal, but I am finding the Super Phat even through a cab sim sounds really rich and nice on its own, without any pre-amp sim.
I really like it, it is always on.