i'm using the HD800S and iCan Pro with a Yggdrasil and Marantz SA8005 as source. it's quite the endgame setup for me and i'm thoroughly satisfied. the only add-ons i might consider for later is the ifi dsd pro, the ifi estat unit, and a pair of stax headphones.

They're not the same (one is amp only) but i doubt the amp section of the WA8 will be any better than the iCan Pro.

looking forward to some listening impressions from the RMAF 

Hope it works well with Stax

looks like it 

i have both the bryston bha1 and the ifi ican pro. you are right about the bryston being slightly bright and harsh. the ican pro is the smoother, more detailed, luscious, and holographic sounding amp of the two. the ican pro is also clearly head and shoulders above the ican se.

I've been using the iCan Pro with the Yggdrasil and HD800S for a bit and the combination is stunning. Think of the pairing as lifelike hyper detailed DAC meets lush, highly musical amp and completely honest headphones.

I'm using balanced cables at the input and output sections of the amp. I have no issues. The amp does not slide around.

An electrostatic module for the iCan Pro will be out which gives the amp greater versatility than the Taurus or MZ2. A Stax L700 with the iCan Pro should be pretty sweet. :D

Looking forward to the day when the electrostatic module is out. Can't wait to try a Stax L700 with the iCan Pro.

I swapped out the stock cable with a Nordost Purple Flare power cord. There were some minor improvements. The sound seemed weightier, smoother and more natural. It's also slightly easier to identity micro details in a track. Overall a nice upgrade.

The thing is I'm not sure if the C14-C7 adaptor is supposed to be included. I saw an unboxing video of the iCan Pro at https://www.youtube.com/watch?v=mQf_f2inMYk, and there doesn't seem to be any adaptor in the box either.

  Wow. I didn't get any adaptor in the retail box. Will iFi make it available to the early adopters?

I believe for many that have bought the iCan Pro, myself included, we just enjoy the heck out of it so much that we no longer bother about comparisons with other amps.   

The Yggdrasil with the iCan Pro and HD800S are making magic together :D

Finally, Spotify support for the HAPZ1ES :D

It's likely the DAC section of your Questyle that is the problem, because it's fine when you use another DAC, i.e the Dragonfly Red. You could check out the iDAC2 if you're looking for another DAC.

  I reckon it has to do with the output level of your source. Balanced outputs will sound louder than single ended outputs.  

It's stated in the manual that "Each GE5670 tube has undergone a special rejuvenation process and the tube circuit is specially-designed for long life. Combined, the tubes should offer many years of enjoyment." 

leave it playing in tube+ state and check back every now and then

Schiit Yggdrasil The choice of DAC makes a greater difference than single ended or balanced connections. I first heard the iCan Pro at a shop which was connected to the single ended iDAC2. It was quite decent still.

Yes, impressions over at the iCan Pro thread http://www.head-fi.org/t/795344/ifi-ican-pro-upcoming-dedicated-headphone-amp-release

Tried the Tube+ setting today and there seemed to be positive gains in airiness, texture and resolution. However, the sound also seemed a little thinner and sharper. I know the tubes are still new with barely an hour of use, so hopefully as they burn-in the sound will improve.     

I have owned the Sennheiser HDVA600 and Bryston BHA-1 prior to the iFi iCan Pro. I would rank them in the following order:   iFi iCan Pro >> Bryston BHA-1 > Sennheiser HDVA600   The iCan Pro is the most powerful amp by far, and it exceeds the other amps in most aspects (i.e. detail...

Not yet. I find that the HD800S is not lacking at all in bass or soundstage when driven by the iCan Pro on default settings.