Thanks for the comments guys.
Tom, they ship with Sovtek 6550WE output tubes as everyone seems to have a tube preference

. I have always found the Sovtek 6550 to be durable, reliable tube and I like to have the amps go out with a tube I can trust. Besides, with the 400+ hour break-in required on the Reference and Platinum, who wants to burn up expensive tubes during this period.
I do like the Shuguang tubes and think you wil be very happy with them in your Platinum 3205. Let me (us) know your thoughts.