BAT Rex II VS Conrad Johnson ARTSA

I'm trying to upgrade my system. Currently have Cary 120sMKII with Cary SLP-05 preamp. I see a BAT RexII and CJ ARTsa on Agon for about half retail. I want to spend around 10k so wanted opinions on these two or other tube amps I should be looking at in that price range for top quality used tube amp that would be clear upgrade to my Cary.  Thanks