It's one of the cheapests phono preamps you can get with a gain knob. I choose it for that reason, however I thought it was a volume knob, and those are different things. However it was still useful considering I had no knob (or at least «easy to reach» knob) to control loudness in my first setup, where I had the turntable conected to this and then directly to active speakers. The gain knob only lets you adjust the strenght of the signal within a certain range. Doesn't let you, for example bring the sound to a «mute».
Either way I still have it in my current setup, and even though a better one can impact the sound quality, I find this one perfect enough, as there are other components (like the speakers and the needle) that have a much greater impact in the final result.