As much as I like the Beta 22, I probably won't go into that route because of my concerns dealing with after-sales service and things like that.
I also apologize if my tastes are rather esoteric. I am relatively new to headphones so my benchmark is a little different to you headphone guys. For reference, I like Krell and Mark Levinson equipments the most. :-)
A violectric V200 or Luxman P1 might work for you.
There is also the Burson HA-160. It does make the HD800 a little flabby in the bass, like a tube amp. But on the other hand it is very warm and inviting and has some punch to it. It is a bit of a strange amp, and very seldom recommended for the HD800. But hey.... if you don't like the Taurus and MK2 your tastes are clearly not like other people so what the heck, give it a try.
Thank you for the suggestions. The Luxman may be difficult to audition directly but I know dealers who have Vioelectric and Burson amplifiers so I can give them a ring and arrange an audition session. Seems that they have no balanced outputs though?
If you like the B22 sound, then you may also like the V200
I consulted the builder whom built the very impressive Beta 22 that I had the pleasure to listen with and he explained that the first one has too little voltage gain and the second one has too much gain. He also said that he does not recommend active ground scenario and instead go for fully differential balanced config.
Still I thank you for the suggestions.
Thinking about it seems the options for high-end solid state amp is limited when it comes to headphone world... perhaps I should consider tube amps after all.