That Bryston only has 180W into 4 ohms. I think a Bryston would be a good amp to drive PSBs, but remember the Synch One's impedance drops below 4 ohms, so I would think it might need higher power; it depends on the size of the power supply of that amp. If I remember correctly, you were missing the fullness of bass with your other amp.
But, I'll bet the 3BSST can drive your Synchs.
But, I'll bet the 3BSST can drive your Synchs.