Which would you choose; Pass 250.8, arc 75SE or luxman m900u?

OP: I have the ref5se paired with a pass x250.5. Awesome details from arc matched with the fast and deep x250.5 - I am in heaven! I’ve pondered an all arc system - but fear it might be too clinical. 

@guyl - good to know you found the move from X250.5 to Ref 75 rewarding! Perhaps I should consider that move. I spent so much time talking to ARC and Pass before I made the decision to pair my Ref 5 SE with the X250.5 I was initially discouraged by the 20K min required i/p impedance that ARC expects. They pretty much said that thats a statement that isnt necessarily valid anymore. Apparently the ref 5's o/p impedance doesnt swing much beyond 1500 ohms and a 20K i/p imedance on the Pass was more than sufficient. Curious - what improved when you went from X250.5 to Ref 75? Thanks!