So you think the better options are either:
1) internal soundcard using analog outs
2) internal soundcard using digital out
3) external converter using something other than usb power
???
I'm not trying to be flip, just trying to understand your post.
Here's the thought. Most inexpensive internal soundcards are not adequate. Something like your Freeway device looks wonderful, but is too expensive for me, especially considering the fact that I'd also need a DAC.
An external converter using usb power is less expensive than something like an RME card, yet removes the DAC from the noisy environment of the computer.
Kill two birds with one stone. No need for USB--> SPDIF converter and I also get my DAC.
You think the silverstone solution would fail miserably because it runs on USB power?