Haven't done the whole thing yet. Planned to use the Stratus of another local Head-fier (mine got sold in part to fund Stellaris) but it got shipped back to Donald for upgrades just when my time off came up. Then I started traveling for work again. Im trying to get it back in for the Stellaris \ Stratus section. Of the testing I did with Afficionado, ZDS and Stellaris my findings so far were: Stellaris is my preferred amp for clarity & definition, speed, features, and general 'hi-res' listening. Its the most versatile in that you can swap out the tubes and shift the sound palette without losing the speed and tonality. Make it warmer, lusher, etc. Most of my headphones sound their best of it and I have yet to hear it actively make any of them sound worse. Afficionado & ZDS are different beasts. The ZDS sounds like a ZDS, not going to go into that. Afficionado is definitely more versatile than it is, not as slow, not as much impedance in the picture from what I'm hearing. More rounded as an amp, better for rolling for sound ( for me anyways). Afficionado v Stellaris: The Stellaris is winning by taking fuller advantage of the tubes. Same tubes are performing better on the Stellaris. But obviously a huge price difference. Once again, the tubes make the biggest difference on each amp and make sure they are fully warmed up all the time or your tests are useless. As I was typing this I heard the Stratus is back in town, now plan to get that and do some listening over the Holiday. I believe the Stellaris is better, will like to hear it v. the upgraded stratus though.