Yeah I played with it a good bit, During my review time of the HD700 I left in on the lowest setting and even toyed with the highest setting and though I completely agree the lowest ohm really helped out, but when I'm in reviewer mode and really listening to every detail a tube amps distortion does become apparent, but in my everyday musical enjoyment I absolutely LOVE the sound and its welcoming warmth. The Solstice was one I came a split hair of buying my only change was most of my headphones I plan on purchasing are all higher impedance.
Headphone Reviews and Discussion - Head-Fi.org
i also ordered an amp from them, though a different model (solstice)
did you changed output settings of your amp? it has 3 settings I believe and they can alter the sound quiet a bit. i heard lowest setting 0.1 ohm almost makes it sound like a solid state amp.