I was looking at the micro server but I already have a NAS being used so might give this a try.

I think its a case of trial and error.

NAS will be fine if you're just streaming, low power as well.

I've got a Microserver so I can use it to download, backup automatically, RAID backup, etc. They're only around £100 after cashback as well :cool:

[Edited on 08-11-2012 by noshua]

For music i can't see any real cons; as you said, it saves powering on the PC and most NAS boxes are power efficient to run continously.
Only issue i can see is if you're planning to stream video and need to transcode as you might struggle with processing power on lower-end boxes.

I have all my music on my NAS which then runs through itunes on the laptop
Yet to find any issues with it tbh

Also have films and tv series on there. Bought a raspberry pi with the intention of running xbmc on it but TV streams it directly so never bothered setting it up

Debating wether to move all my music onto a NAS,

Use iTunes on my main PC for all my music and sync to iPad / iPhone.

Now running XBMC in the living room, thinking of attaching a NAS box to the the network, but not sure if i should just leave all music on main PC and stream it to XBMC, means having to boot the PC up if i want to use XBMC, and im thinking of putting a secondary XBMC in the conservatory.

Pros / cons people? anyone using NAS with iTunes and XBMC?