i have one and it is a good pedal. with a les paul you can go from a good classic crunch and grind to a biting growling attack. its just a matter of mixing your amp/guitar settings to the pedal. its not too good on the blues but i might not have the right mix yet.
i dont know if this happens on all of them but if i try to use it with my fender strat(60's special reverse s/s/s) i get a horrible whine and feedback like you wouldnt believe. i have traced the problem either to the pick ups (stock but they dont do it with my other pedals.) or the pedal its self.
They say the END is near, but I'm Tired of waiting.