Ran across this blurb and wanted to archive it. This is taken from Mac at DIYSB

Rule of thumb, as long as the you match the right hfe for a fuzz it will sound good.

q1: hfe=70-90, leakage <50ua better but can be up to 200uA
q2: hfe=90-120, leakage <200ua but 300-400 may work.

q1 should be low leakage so as to have 4.5v at q2 collector with a resistor closer to the original 8.2k.
Also q1 has a much great effect on the bias resistors than q2. Just finger heat the transistors one at a time and watch what happens at q2 collector. Or if you bias the circuit with 4.5v at q2 collector, and you replace q2 with a leaky transistor ot much higher gain, vc2 will move a little. Put the original q2 and replace q1; vc2 will jump a lot.

About the sound, I have some american and japanese transistors with the right parameters, ie, the ones above. I know some may say I’m crazy but there are differences. Some are brighter, some darker, some have more mids, etc. But they all have fuzz nicely.