I also own the V. Vlad does not recommend swapping the tubes as his original tubes selection sounds best. I bought quite a few back up Russian tubes from Ukraine on ebay. Perfect transactions and inexpensive prices, about 3 weeks for delivery. I saw Vlad at the Round Rock audio show and discussed the VI. I first was gonna pull the trigger, but after thinking it over, I don't want any extra amplification from my dac, like the VI has. My system does not need it. The V is perfect in my case. BTW, Vlad is as friendly a dealer as you'll ever find and will always be willing to work with you.
