This long discontinued distortion pedal is in need of a well deserved reissue. While never as wildy popular as the TS-9 Tube Screamer, the SD-9 always held its own by giving off out more agressive and somewhat grittier vibe. It's basically like a TS-9 on steroids. It's one of the more dynamic distortions you'll ever play through. Subtle volume and picking changes are responded to and you can take this from light crunch to a full shred depending on your playing. Unlike many other units, this can sound tight and focused at one setting and open and airy on another. This wide pallette of shades and colors has always attracted a a rabid following including the staff here at the GuitarGeek test facility. There are still great deals to be had on these bright green goodies so don't be afraid to lay down the cash if one pops up.