It’s no secret that it’s based on the Tube Screamer, but its modifications are significant enough that depending on the control settings, it can either sound nothing like a TS or exactly like one.
However, the Soloist is not an exact copy of the circuit inside the Duellist. A “Body” potentiometer has been added, and the “Fat” toggle mode has been swapped for the new “Edge” mode. The internal DIP switch has been removed, so the “Warmth” and “Asymmetric” modes from the Duellist are not in this circuit.
The Gladius unifies these two circuits, adding the internal DIP switch from the Duellist so that the Warmth and Asymmetric modes are once again available. Otherwise, it’s a direct adaptation of the Soloist standalone pedal.