My first Bryston Amp was a 4BST and at the time I had Kef 104/2s which had MTM in addition to coupled woofers. It was a great sounding combination although the Kefs were a bit laid back and I had to turn the volume up to bring the midrange to life.
Also, my brother has a 3BST and for a long time he was using a pair of Dynaudio Gemini's which were MTM kits with Dynaudio esotec drivers. Another great sounding combination. The Geminis had more lively open midrange than the Kefs, but it was smooth clean and resolute.
I am not sure that either the Kefs or the Dynaudios countered an inherent strident characteristic of Bryston amps. I have heard others use terms like strident and bright associated with Bryston, but I have not experienced that with either the 4BST or my current PP300SSTs.
Al