This box provides a crazy variety of envelope filter options... most that I've gotten are still pretty useful. It takes up more than its share of space on a pedal board, but it begs to be tweaked. With the right blend and other settings, this box really funks up the mix. It's adds a lot of musical color. Figuring out how to set the Q and Sensitivity for the best effect requires a lot of experimentation. On the one hand, you might think that better instructions would be helpful; on the other hand, you might say it's better not to limit your creativity.