I had the opportunity to visit Alain Caron (AC) in his studio while he was transitioning from Roland to MarkBass.
He explained to me that the Roland D-Bass combos were designed with his feedback and the goal was to develop the most neutral combo possible, with the technology of the time. They came up with the FFP tech, which is basically a DSP similar to what was found in studio monitors. In SuperFlat mode, you had as much as a FRFR system as it was possible in those days. As Roland was moving out of the professional bass amp market, he was approached by MB...
At the time of my visit, Alain was in the process of A/B testing the MarkBass prototype combo with his reference for what he was looking for: his own studio monitors. This is what he uses at home. This is what he wanted to have on stage. No coincidence the design is similar to a PA system (bi-amped, powerful tweeter, etc.)
With the controls "neutral", this is probably one of the most FRFR combo available, plus you get the MB coloring on demand. Love this combo!