I second the glowing recommendation of the Peter Daniels AudioSector DAC. The drawback to his DAC is that it only takes one input, whether that's SPDIF coaxial, optical, or USB. What you're getting is a minimalist DAC that makes few sonic compromises. Peter will sell you the DAC for the cost of the DIY kit plus a reasonable assembly fee if you want him to assemble it for you.
It is a NOS DAC, it is very musical, and sacrifices only a little in the way of detail and dynamics while presenting a very organic, natural sound. On balance, I have found it superior to Benchmark, the Electrocompaniet ECD-1, the iRoc USB DAC, the Citypulse, the Zhaolu, the Channel Islands, and I could probably find a few more to add to the list.
Of course, another solution is to scrounge together an old PC, setup iTunes, get yourself an iPod Touch, get the USB version of the AudioSector DAC, install the iTunes remote software on the iPod Touch, and I think you would have yourself an even better music system. USB, in my opinion, is superior to SPDIF, and you won't need any jitter reducing component.
I have not heard the Stello, but I recall many posts singing its praises. It's certainly more flexible than the AudioSector DAC, has built-in jitter reducing functionality, and has a wealth of inputs, including USB.
tvyankee: I notice that the Stello has an upsampling switch. Does that mean it has an upsampling mode as well as a zero-oversampling mode? Also, is the USB input a USB -> I2S implementation, or does it convert USB -> SPDIF -> I2S?