Is USB overrated as decent digital source?

Ok take for a moment that what your really asking is for some sort of Digital source to be changed to analog. Leave the USB out of it to begin with. USB is nothing more than a type of connection that will support a transfer rate of about 50MB a second. Are you interested in the dac, the connection, or how it gets interfaced with your source? All of them?

Then mass produced items get poor (generally) dacs the most expensive get the better dacs and better caps and better designs from the input (USB) to the output RCA.

IPODS do not output from USB they take input, they output analog which makes the ipod a non source. If you want to use the USB DAC from your computer then you place a whole additional piece in this puzzle as your computer must be fast enough to allow unbroken transmission to your DAC. This is easier said than done especially depending on the compression or non compression of your source and how the USB DAC supports the USB interface.

How does a winning combination sound? Better than most will admit, especially a audiophile, as we tend to hold on to the things we know, quite hard sometimes.

I see alot of comments about the speed of USB but not enough about all of the pieces. You can certainly choke a PC or MAC with streaming music, as the Hard drive speed, Processor speed, amount of memory, and the USB version all combine. You must consider all of the parts that work in unison. USB has buffers at each end and performs error correction, no jitter that way. You must take into consideration all of the parts including the USB DAC when designing a music system based around a USB DAC and PC.