EQing is also important to make your distortion sound heavier..
personally, my metal muff is at 10 o'clock only while my sonic glory is at 2 o'clock..
eq on metal muff is high mids and bass (around 2-3), lower treble (10)..
i prefer bassier kinda distorted and overdrive sounds, and use my pickups for trebly sounds..
my amp distortion is hopeless though.. lol..