PS AUDIO bhk pre-amp vs upper level reference pre-amps?

I’m looking for some feedback from people who have replaced their more costly reference pre-amps with a PS audio bhk or have heard it up against such units.
Im currently using an Audio Research ref 6 between a PS audio direct stream memory player and dac with the the bhk 300 mono amps. Would the synergy with a bhk pre in my system be worth replacing my pre?
Mike