Have it for about 3 years now. The boost is insane! at 2 is already too loud. But I love it. Makes my entire chain sound better (ballsier). But I only use the gain knob at very low setting (max 3) as I find that it gets harsh in higher gain setting. I use the Green Rhino before this pedal and just engage it for a thicker, more aggressive sound and that's without the boost.. The HDB provides two additional gears to my already slightly driven sound: ballsier and insane, without added compression.