Excellent! I loves me some muff fuzz on my boom stick!
Seriously though, I do like to mix a little clean in there too. Wether it’s by way of some kind of parallel loop(boss LS-1 works ok), splitting off a signal before the dirt and routing to another amp/channel, or via a pedal that has a blend feature built in(like his deluxe bass big muff).
Edit: I really like a Rat pedal on bass too, these days.