Which pwr amp to go with Classe DR6?

Which power amp works best with Classe DR6?
Krell, MacLevinson or Classe.
Should I change to tube pre + ss poweramp Or the other way around?
I run a classe dac1 to a classe cp-50 to a classe 101. I love going balanced the whole way through(BONUS). I think it sounds great personally.
I'm running mine balanced with a Bryston 4B NRB. Good combo for speakers that aren't too bright and need some current to help them along.
i own the dr7 pre amp..and was lucky to find two dr3 amps/25 watts class A(wich i run in stereo//80 lbs each).i measured there output @~ 40 watts rms(probably not pure class A)+pulling about 2.8 amps each .(there great in the winter/i don't need to turn the heat on)the headroom is~8 which is hard to find in any amp.i was told they were designed to compete with a certain mark levinson amp.they also made a dr3vhs which is the 40 watt version(monster@120lbs)..it's tough to find a better amps for the price..
The matching Amp to the Classe DR6 preamp, was the DR25 Amp and the S700 Classe Amp