I bought this about six months ago for usage with normal dynamic microphones and with my keyboard to give it a bit more warmth. I say it shockingly good as if I pick the unit up when in operation it give off electric shocks! which I imagine is a grounding issue. I imagine it doesn't affect every unit, but be aware as its happened to my unit.
Apart from the fault, I have found the unit to be very versatile and has lots of different settings, for different applications. doesn't break the bank either,