Well, I have had it set up for two weeks now and it has settled in nicely. Although Vidar appears to not quite have the sense of space of the Pass X150, it easily bests it in bass control and lack of distortion at high volumes. In fact, I put Vidar into protection mode while playing Kodo's Oki Age. At first, I was disappointed that it didn't get that loud, but when I pulled out the dB meter, it read 115!
What I took for lack of Volume was actually lack of distortion. The fact that I have to compare Vidar and Feya to an amp/preamp costing more than 5X the price speaks very well of it. It is not just a great value, it is a great setup in its own right.
@USBlues, I know that we had discussed the relative merits of NOS vs new Tung-Sol tubes, but after spending time with both in my system, I find that the vintage RCAs give a better sense of space. I think you may agree, despite both of our feelings about jumping in the NOS rabbit hole.