Audion Sterling Plus upgrade


I'm looking for a SET power amp that takes tubes like EL34, KT88, KT77 and 6CA7. I have my eyes on an power amp from Audion Audio; the Audion Sterling Plus which can use all these tubes, and some more. The few reviews I've seen are very positive.
Then I discovered that there are upgrade versions. But are they really worth the cost? The first step on the upgrade ladder is called Insignia, which has silver wiring, higher wattage components and tantalum resistors. But it costs. Compared to the standard version which is 20 500 DKK, you have to pay 36 000 DKK for the Insignia version. Can it really be worth these kind of money?
I haven't looked further up the ladder :)

Any thoughts?