I know the Tanaka damascus is "straight carbon steel" and I'm all but certain the Yoshihiro and Kajihara are as well.
I've never seen:
Of the others:
The Kohetsu is a great laser style knife....really a freak of a great deal IMHO.
The Tanaka is a perpetual favorite if you're after an all carbon, damascus clad, medium weight gyuto
The Kajihara is quite similar to the Tanaka from what I can recall (if I'm recalling the wrong knife, don't shoot, I'm unarmed)
The Sakai I recall being a good knife....but not one I'd pick from this group
The Konosuke HH is $8 less than the HD2.....I could never justify buying the HH over the HD....NEVER.
Which I'd buy would kind of depend on what I was after.
You didn't mention a criteria for heft (i.e. laser versus medium weight versus heavy weight), so:
If I wanted a laser.....I'd get the HD2 or the Kohetsu
If I wanted a medium weight, I'd get the Tanaka
If I wanted all of your criteria met, I'd get either the Kikuichi (I've heard good things about it, but never seen it) or I'd maybe try this:http://www.chefknivestogo.com/kar2gy21.html
Again, heard good things....but not actually tried it.