Well see,
I just bought a Fuzz Face replica (Arielfx.com, he is great BYW) and tried it out, and it sounds cool but still - not enough.
It has not enough gain/sustain and since I don't have a Tube Amp and can't play on high volumes - what this guy suggested me is to register this site and look for a volume boost (I don't remeber the name) so I can put it in front of the Fuzz, this way the fuzz gets bigger signal to fuzz and it may have more sustain.
Isn't that true? and isn't there a transparent volume booster? because that's the only thing I need to control.
The idea of a transparent booster, overdrive, or other pedal is a subjective one. Any time you put your signal into any booster, it becomes precessed, if only by a few caps, resistors and a transistor.
That being said, a simple one-transistor booster with few components will fit the bill perfectly, and will be easy to adjust if it isn't to your initial needs and/or liking.
For a 1st project, try Aron's booster, then go from there. WARNING: Once you build one pedal successfully, it probably won't be your last.
Just think, you can build your own fuzz pedal to your exact needs, and fuzzes are simple to build.