I bought a Warp Factor used years back...I have a clip of it with the ValveJr somewhere...here:

Anyway...I gave it to a friend over a year back, but a few days back I happened to remember it and asked if he used it, and since he didn't I took it back. And...well, I hardly ever use distortion as is, but this thing is TOUGH with the Ceriatone rig. It's so beefy - maybe because it has it's own 18W power source - but it gives no noise and it gives marvellous 'screams' especially harmonic squeals รก la Zakk Wylde. All in all, I've been floored today how great distortion, especially a very 'famous metal' distortion can sound to a guy who uses very little distortion normally. But this thing...it makes solos sound fast and cool.

Maybe I'll have to use it from now on as a lead boost.