Economical alternative to Wadia ipod dock?

I'm helping my 20-something son put together a system. He knows digital; I know analog...kind of. He currently stores the majority of his music on an ipod. What docking mechanism for the ipod would you recommend to feed into a DAC for a best-musical-experience for the buck? From what I can tell the choices out there are the Wadia 170i and ?. Thanks in advance for any ideas you can give me.