I'm not as well versed in Big Muff lore as I could be I suppose but the general consensus seems to be that older Muffs (either the EHX or Sovtek ones) are superior to the newer ones, or at least they are more desirable.
With that in mind I was longing for some of that sweet thick fuzz that I lost when I sold my 90's era Big Muff (like a FOOL) in favor of something that has since itself gone the way of the dodo.
At any rate, after learning that to replace the exact Big Muff I once had with a vintage one of the same era would now cost upwards of 3 times what I originally paid for it, I started looking at some boutique options and that's when stumbled upon Wren and Cuff.
I noticed that they make FOUR different Big Muff clones each based on a particular incarnation of the iconic pedal. These guys are hard core.
I selected the TFR and I never turned back. It's awesome! It's got the right amount of gain/saturation/sustain while still maintaining some semblance of note clarity all the while delivering on its promise of muff goodness. I tend to keep the distortion knob at about 4 o'clock and the Tone knob around noon. I find that if I back off the distortion (like noon or below) I lose some "umph" in the overall tone, but to me, Muff pedals aren't supposed to be especially subtle. Besides, I'll say again that the note clarity to amount of gain ration is pretty impressive and what I mean is that even with a rich saturated fuzz dialed in, I can still hear the notes if I play a chord rather than just a wall of buzz, which to me, is a big plus. My understanding is that they consider this to be a medium gain pedal, so if a wall of buzz is your thing, they might have that in one of their other pedals! It's well built and Wren and Cuff have an exemplary warranty policy.