Yes that wonderfully aggressive fuzz box with the really obnoxious name. Can't believe I'd never owned one of these before. Now that the BYOC "Large Beaver" is complete, my other fuzz boxes only collect dust. I chose the "Ram's Head" era design, and had considered socketing the clipping diodes, but decided the included mods were enough.
Building? I'm glad this wasn't my first build, but an ambitious first-timer could do it.
The sound? Most people associate the Muff sound with Smashing Pumpkins and Pink Floyd and this pedal delivers.... definitely best through a somewhat stressed tube amp. Otherwise it can just buzz like a swarm of angry bees. Used with a Les Paul/neck pickup/tone control set to zero, classic haunting Fripp-like tones are easy to acheive.