Not sure about the guts, but tonally the three-way clipping switch gives you three distinct flavors of fuzz, from low and barely compressed woofy fuzz to thick muff territory (especially with the bass boost on).
So far I am using it as a sort of muffish tone. I am running it on the highest clipping mode, right at about 3 o'clock where it starts to gate a bit, with the bass boost on. I keep the Level pretty low to push the gain up so high, and the tone knob generally stays between 12 and 3 o'clock depending on the guitar.
I've had the chance to play a lot of really nice fuzzes lately, and this guy was my favorite hands down. In fact, I highly recommend all their pedals aside from the Transit which I haven't tried or really would know what to do with it. They are all built in the US and top out at about $200. The Voyager is a pretty badass OD in the TS territory, the Mayflower is a really nice Timmy-esque OD with Bass and Treble controls, the Iron Horse is a straight up beastly distortion which I might also add to my board soon and the Deep Six is a damn fine compressor which I prefer over the Keeley Four Knob. The Janus I personally have no use for, but it does make interesting noises.
It's quite possible I will have a the Jupiter, Mayflower, Iron Horse and Deep Six on my board sometime soon, with the Voyager being a maybe depending on what if I want to use the Mayflower as more of a boost and the Voyager as an actual OD.
Also they all look cool as fuck:
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