Stello is very highly regarded and a very popular dac around here, I haven't heard but did extensive research on it, always gets excellent reviews.
I personally bought the MHDT Paradisea, a non-os tube dac for $600, they are sold new on ebay. If you like a warm natural almost analog sound and very musical I would check that out, can't say how it compares to the DA100, except that I am very happy with the Paradisea. Voices sound like voices through the Paradisea -HD650, I always find with most dac's it may be hyper detailed but still sound artificial, the realism of Paradisea makes the music more emotive to me, so thats my two cents.