I've built most of them! And I use a commercially-built Chase Tone Secret Preamp on my board at the moment. Though if you swapped it with any of the other ones I have (PPCB Clandestine, Aion Ares, PPCB Episode, MBP EpiPen) without telling me, I'm not sure I'd know... They all add that little something. I'm not sure what it is, but it just sounds better with one on. Most of them don't give you a huge volume boost, but that's not really their purpose. I do tend to like the versions with the high/mid/low voicing switch, as it becomes more versatile depending on the guitar or amp you're using.