Is Reactor 600 high end?

[Snoopy8]

I could probably get better result with a pair of Classic Premiers (or Golds), but the price difference is too big for my budget at the moment.

If you compare the Golds side by side with the Reactors, you can hear a difference. But listened on their own, the Reactors will beat or match many high end systems that I have heard. And Audiolense will improve things further.

I agree the Reactors are value for money. 

The chain will be Roon->EtherRegen (B->A)->Reactors.

That would be my suggestion on how to use the ER. You can also compare A->B and use PLC.