Audio Research Ref 6 vs 6SE

I have heard nothing but good things about Trent. He explained their metal remote manufacturer had suddenly stopped making them or when they out of business. He wants to have hands on control of the company. I think the stint with MacIntosh may have been a good thing… they are finally using contemporary electronic design and layout equipment. But he is not a large corporation… he want excellence. I think the divorce will be good. He immediately promised me metal remotes for my components when I complained about the plastic ones. 

I apologize for hi-jacking the thread but I am approaching 1500 hours on my Ref 6 and will be buying 6H30PI's. Seems like my choices are ARC and Upscale. Any other suggestions for top quality versions of this tube?
I love Upscale for tubes so I will probably just pull the trigger with them. They offer an "ARC selection" grade but are out of stock of EH version and just have the Sovtek version (which is likely fine). 

i got my recent set from Johnny R @audioconnection , great service and tubes

I have used ARC, Upscale, and The Tube Store. For my ARC equipment I usually go to ARC. They have meticulous break in procedures, and also, I like to support the company. But you can save some money going to Upscale. 

I have the Ref 6 paired with a Bryston 4b cubed.

Would appreciate feedback on successful amp pairings to the ref6.

 

Thanks