I use QNAP NAS to store my iTunes library and Twonky pkg on QNAP as DLNA server.
I also use Metadatics (OSX app) to manage covers and other metadata when not properly set by iTune.
All works well together as long as you don't have DRM protected tunes.
Thanks for your opinion mbolo01. what model of qnap are you currently using? Do you have purchased music from itunes? Purchased music from itunes is what I want to sync with NAS so the Moment can stream it.