The Audio Research LS26 and REF3 mate extremely well with the Theta Amplifiers and meet all of your criteria. I listened to the BAT VK51 SE (which he owned) and the ARC REF3 in a system with the Theta Citadels and there was no comparison. The REF3 beat out the BAT in every way. Again, this is personal experience and YMMV.
The owner of that system also tried the BAT REX and decided to sell his BAT and bought a REF3. I recommend that you try to listen and decide for yourself as everyones taste is different.
The owner of that system also tried the BAT REX and decided to sell his BAT and bought a REF3. I recommend that you try to listen and decide for yourself as everyones taste is different.