The Fireball works pretty well with overdrive/distortion pedals - but I've never tried a Fuzz Face or a Big Muff.
On a few occasions I need a crunch channel, so use a Marshall Guv'nor pedal and it works very well.
What sounds are you after/what music do you play? The main selling point of the Fireball is its fantastic dirty channel - if you plan on exclusively using the amps clean channel with pedals, it'll sound good (the clean channel is surprisingly good), but kinda avoid the purpose of owning a Fireball.