I bought this in hopes that it would give me a subtle overdrive so that I can color the tone without adding much of an actual overdrive where it is not needed. This pedal has A LOT of gain. A lot more than I expected, even at minimum gain.
The sound itself is pretty good and usable if you like high gain stuff. I can't comment if it sounds like an actual Dumble, having never played one myself, but I do have some Dumble emulating pedals. This one has a different character than for example NUX Steel Singer which I do think is a little bit better than this one, because of the overdrive range.
The sound is also very bass heavy and quite dark. I am playing mostly strats with Vintage pickups and even those sound quite dark and give me TONS of bass with this pedal. If you tame it with an EQ, and work with the volume knobs on the guitar, this one can deliver some good tones.
I hate the phrase, but for the money it is fine.