I only ever use the drives for lead and higher gain stuff to push the front end of the amp. The drive models I use are mainly the Klon, EP Boost, Big Muff and occasionally a Fuzz Face into a fairly overdriven amp. I can understand what you mean with the Big Muff, I use the EP Boost in front of it going into a clean amp, the boost really thickens up the sound and adds power. I've never been a huge fan of the TS-808 but in my experience, I've had better results using the Helix model than when I've played the actual pedal into an amp.