I haven't heard the DA10, but own the DA11. It's a nice DAC which sounds better than I expected. The headphone output works fine with low impedance cans, but I don't like it very much with the Senns, though it sounds clean, maybe "too much".
IMO it sounds more "natural" than analytical, it doesn't seem a pro unit. In addition it sounds quite consistent no matter if you feed it using Toslink, AES/EBU, SPDIF or USB. I find it listenable even using the optical connection, so go figure.
Mr Monkey, I think you might enjoy it, but you already have many good DACs. I'm not very sure it will "outperform" them though I'm quite sure you won't find it grossly inferior.