BAT Vk55se or Atma-Sphere S-30 MK111 withal all the upgrades ?

@blindjim thank you for your thoughtful response about each of these amps. I have made the decision to go with the BAT because A) brand synergy, B) The Atma M-60 monos, although beautiful and detailed were slightly thin in areas, less body, or"meat on the bones" as they say. C) Less fussing around with tubes and fuses, and of course this was the S-30 so even less power there. I think both companies are great but so far I like the overall sound of BAT and I am hoping that the 55 has nice transients, open space around instruments like the M-60 but with more weight. HA, we will see . 
Best, Greg

I think the Atma-Sphere would add more speed, more transparency and larger sound stage, all of which I am told the Tektons excel at. 

Jim
Not a dealer for any of the mentioned products but have experience with the amplifiers.

I think Tekton offers an 8 ohm version which might suit tubes better.

Hi, you may be interested to join this facebook group for Tekton Design speaker owners in case you have questions or would like to know more about their first hand experience with them, and the electronics they use to match with their speakers:

https://www.facebook.com/groups/135142323767796/

There is an 8 ohm version of the DI, which is the one to use with tubes in general.