You can sometimes find an AMB y2 used for ~$200. It has optical, USB, and coaxial ins. Not to mention digital outs, 3 analog outs, and it's USB or wall powered and has a small footprint. Makes it a lot more versatile than some of the others you listed IMO.
I had it with Magni, Lyr, and Valhalla coupled with a HD600 a while back. It's a great combo.