I previously bought the smaller CL-1 model, but needed to mic up a Cahon drum, with a dynamic mic in the rear sound hole, and another one at the front for ambient sound.
The CL-1 does a wonderful job (see my review on it), and it works so well on all dynamic mic's that I wanted another so that I could use more than one mic at the same time. It is a minimalist design, with none of the indicator lights or switches you would expect. All you get are two input sockets, and two output sockets, but the effect it has on your dynamic mic has to be heard to be believed.
CAUTION: Does not work with condenser microphones.