Amp upgrade from Bryston 4B


I currently have Thiel 3.6s main speakers driven by an older Bryston 4B amp that has been a good match. I have been considering upgrading the Bryston 4B amp to used Bryston 7B mono blocks(?) However, the Bryston 7B amps have had mixed on-line reviews. Any other recommended amp upgrade recommendations in the $5K used range that would be a good match for the current Thiel 3.6 speakers and potential future Thiel 3.7 speaker upgrades?

OTHER EQUIPMENT: I am setting up a 5.1 surround system with an existing Rotel 985 5 ch amp to drive Thiel SCS4 center and Higherplane 1.2 rear surround speakers. I am currently using an Outlaw Audio 995 processor in bypass mode for 2.1 stereo listening.
128x128dal0wol
I believe some say the 14B sounds better. Don't hold me to that, however. According to Bryston, the 7B has more capacitance than the 14B, plus you can run shorter speaker cable, always a plus in my book.
Or SST2, that's not a bad, and cheaper, idea as well. But stuff like Pass Labs is in another league.