I use the Peppermint Fuzz on Ch2 in Edge and it's thick and fuzzy. Easily my favorite fuzz for the kinda sound I'm shooting for. Set up channel 2 on edge, run it around 2pm gainwise and 12 o'clock+ on the eqs (no graphic for me) and you can go from a vintage amp crunch (that cleans up with some guitar knob tweaking) for rhythm that gets pushed off the cliff with the fuzz.
Also have a Bluebeard fuzz that sounds killer on that channel/setting.
Others I've tried: Big muff wasn't really my thing, Fuzz Factory was good, but over the top. Germanium and silicon transistors seem to be the way to go (not had much luck with other analog stuff...haven't tried modeling effects)
QOTSA may need a pushed bass amp to get that sound...and some weird harmonizers/octaves.
Good luck, man.