I’ve owned the Model T internal passive & the Signatures both active & passive, also the Mini Ts. Bryston makes an excellent speaker, I recommend them to everyone. I have since moved on as I like to try different speakers.
Passive triamping isn’t the best but you’ll be one step closer to active.... my opinion a couple of 2.5b3 and your 4b3 will be sufficient but you could go with the 3b3 if funds permit.