I don't have a lot of time to write a full in-depth review, and I only have about 2 hours on the amp so I haven't gotten a full sense of it yet.  I will change the pro's and con's if this change drastically, but I doubt they will.
 
***** I'm using Telefunken ECC88's *****
 
***** $680 is the price I paid for parts + case + accessories only, not including the labor I did on it *****
 
Basically, this is an incredible amp.  It has detail that is unmatched in my experience, with incredibly lush treble.  A very smooth midrange presentation is well balanced and neither forward nor recessed.  The bass is neutral, as is the rest of the presentation.  
 
There is slightly tubey sound, but not nearly as tube-like as the all-tube Bijou.  Therefore, it isn't as warm (more neutral) as the Bijou.  The Bijou is more musical, but the EHHA Rev A has a drier, more natural sound.  The bass is a bit warm in the Bijou, so the EHHA Rev A sounds almost bass-light in comparison.  Nevertheless, the EHHA Rev A isn't rolled off -- its just more neutral.
 
All together, I'm ecstatic about the EHHA Rev A.  The detail, clarity, neutrality all add up to be one awesome amp.
  

Mods can you delete this?  I'd like to save Thunderpants for Smeggy personally.  He deserves it.

Still in the works.

Got these on Amazon for $285.00 while there was a deal going on. 
 
These IEM's are great.  They have a healthy amount of bass but its still more or less detailed.  The mids are very nice to listen to, and the highs are very separated and detailed.  
 
The lower end sounds a lot like my HD650's.  The mids are hard to compare to anything, and the highs are almost as detailed as my K701's but have the sweetness of my HD650's.  Its a nice compilation all together and I highly recommend them to someone hoping to spend under $300 on an IEM.

Note: Price of $350 is in PARTS only.  You've still got to build the thing.
 
I don't really have time right now to write a full review, but there is a great review done by Skylab here:
 
http://www.head-fi.org/forum/thread/286709/review-cavalli-audio-bijou-diy-tube-headphone-amp

Well, my AD700's just came in the mail today.  I've gotten them merely minutes ago and I'd like to post up some initial impressions. 
 
First the bad:
 
- I'm used to wearing closed headphones, not open air headphones, so fitment was a huge issue for me, and its going to take a while to get used to.  The headphones are meant to float on your head, not attach to it, so this was very different than what I was used to.  I don't like how they sit on an angle on your head, and how easily they can move around.  I think I might try the rubberband trick on the headband to tighten it up a little bit.  They do feel light and airy when you wear them though.  You have to wear them lower than standard closed headphones, which will also take a while to get used to.  Once you play around with fitment I found they fit better, its just not as easy as my closed pair of M50's.
 
That's really the only bad thing I found about these.  Everything else is great.  The pads are huge and soft, the sound stage is fantastic, the sound itself is terrific.  I have to agree with others when they say this is the best headphone for $100 or less.
 
In terms of audio quality, the mids and highs are great and clear with only very little sibilance.  The bass is freakishly accurate and clear.  Its great.  I'm no bass head so I don't mind not having overpowered bass like my M50's do.  I prefer these for sound MUCH more.  Absolutely amazing for the price.