First impressions:
Yes, it hums. However, you need to be within 2 feet in a dead quiet room to hear it. When used for it's intended purpose, I will never notice it. Note that I use a perfect sine wave UPS with EMI filtering between outlets (I know my power sucks). It's dead quiet through headphones or speakers. You probably don't want to sleep next to it while it's on.
Yes, it gets hot. My $2.99 meat thermometer says 120° after 4 hours (don't laugh, we use the same thing on multi million dollar mainframes). A question for Jason if he reads this, is there a number where I ought to be concerned?
It's very impressive through my PSB Imagine B speakers. I was concerned about going from 125w to 60w and shouldn't have been. Mid-gain is more than enough. I have no criticism or complaints with the Emotiva UPA-2; but there is dramatically more bass with much finer control using the Ragnarok.
I need to reterminate my Beyer T1s, first impressions are that the WA2 is better for single ended listening with them. No biggie, I expected that. I'm dying to try some headphones that the WA2 can't drive. LCD-3F or HE-6? I'll probably let the credit card cool off a bit, first.
More when I get the Beyers reterminated, I know the Rag is natively balanced.