Mac Mini: Use OSX and Pure Music, or Windows 7 and JRiver?

I am helping my father setup a dedicated music server.  We got a Mac Mini and currently using the 15-day trail of Pure Music.  Is this the best way to go, or would it be better to use Bootcamp and install Windows 7 and use JRiver?  

Also, the DAC is connected to USB port #4 (the one next to the SD card slot).  Is this the best port?  We have also tried port #1 (the one closest to the power button) and found that port #1 had a muddier sound.  

After several days of playing with the Mac Mini and Pure Music trail I have decided to keep it and get the full version of Pure Music when the trail expires.  This is my first time using a dedicated computer for music (my main computer is a mid-tower custom built desktop running Windows 7 and JRiver), and I am happy to report that the Mac Mini and Pure Music combo is a great experience.  I am controlling playback with the Remote app on my iPad, and using OS X's Screen Sharing and VNC Viewer on the iPad as a screen/keyboard/mouse.  

Regarding the USB ports, after more listening I think Port #4 (closest to the SD card reader) seems brighter and has more sparkle in the treble region, which probably gives the perception of better clarity that I mentioned in my original post.  But Port #1 (closest to the power switch) sounds smoother, has a darker background, deeper soundstage, and more music seems more enjoyable and flows more easily.  I think I will stay with Port #1.  Theoretically, Port #1 should sound the best because according to System Information (in the Applications --> Utilities folder), Ports #1 and #2 shares resources with the IR Receiver (which I turned off), and Ports #3 and #4 shares resources with the Bluetooth receiver (I left that on for the keyboard/mouse in case I need it, and to wake the computer).  The port that the USB DAC is connected to should not share resources with other devices, right? 

Anyone else tried the different USB ports on the Mac Mini?  Would be nice to hear your thoughts. 

EDIT: My father decided to keep using his dedicated Lenovo Thinkpad as his media server (music and movies) running JRiver; that is why the above comments were "I" instead of "we" or "him." 

EDIT 2: My current system is: Mac Mini with Pure Music (native sample rate; no upsampling); music is stored on a Firewire 800 external hard drive that has its own power supply --> Wireworld Silver Starlight USB cable --> T+A DAC 8 (Beyerdynamics T1 connected to the DAC 8's headphone out) --> Straightwire Serenade II interconnects --> Octave V70SE tube integrated amplifier --> Straightwire Serenade II speaker cables --> Dynaudio Contour S3.4 speakers.  

Time for a little update of my music server journey.  Over the past few days I have compared three different software: Pure Music, Amarra, and Audirvana Plus.  I found that each one has a different sound; it was easy to differentiate between the software in my system.  I found Pure Music has a warmer tone and the music seems thicker, but it is sometimes too warm and thick.  On some piano music, the ending of one note seems to blend with the beginning of the next note.  I think that because of this warmth and thickness, some details are covered up and gives the impression of rolled-off treble.  

Next, I tried Audirvana Plus.  The sound was the opposite of Pure Music.  It is very detailed, but for some music it was not a good thing.  Flaws in most pop and country music is revealed very easily.  However, it is good with well recorded classical music.  The treble seems to be emphasized.  I also tried the 2X upsampling, but the sound seems unnatural. Audirvana Plus have a more analytical sound compared to the other two programs.  

Finally, I tried Amarra.  I think this gives a great balance between warmth and details.  The soundstage is wider and deeper than Pure Music and Audirvana Plus.  I also noticed that there is more layering, or it is easier to distinguish between the different layers in the music.  Amarra has the most natural sound compared to the other two programs.  I find myself keep going back to it because of the smooth and natural sound.  It is close to my Clearaudio Concept turntable (with LFD phonostage).  

In terms of sound quality, Amarra wins.  But there is also the interface to consider.  Audirvana Plus has the best interface and I did not have a single problem (i.e., no skipping, stuttering, freeze, or unexpected quitting of the program).  Audirvana Plus also launches the quickest and uses the least CPU (even when upsampling is turned on).  Judging from the forums and quick release/updates, the developer seems to be great at addressing problems.  

The next best is Amarra.  I only had one problem when it unexpectedly quick and iTunes kept playing but with no sound.  I have read through many threads on this forum and it seems like Amarra has the most problems and least stable, but other than the program quitting unexpectedly once I did not have any problems.  Amarra also seems to use a lot of CPU (relative to the other programs); about 10%.  But I have a Core i5 2.3GHz CPU and I do not use the Mac Mini for anything else other than music so I do not think is will be a problem.  

The worst is Pure Music.  Sometimes when I start the program and I checked the audio settings, Hog Mode would be disabled.  So now every time I launch the program I have to check the audio settings.  I also do not like the looks of the UI (but that is a minor problem because I use the Apple Remote on my iPad to control these programs anyways).  In terms of interface and least problems, Audirvana Plus wins.  

In the end, I think I will buy Amarra because of the good sound quality, and in my system there does not seem to be any major problems.  I will also buy Audirvana Plus for when I want those details in the music to come up, and who knows, with its quick updates the next version might sound great.  

Would be great to hear other people's thoughts on this too. 

By the way, I usually put the Mac Mini in sleep mode, but whenever I turn my DAC on for watching TV/movies on my desktop computer the Mini would wake up.  (The DAC is connected to the Mini via USB, and connected to the desktop computer via coaxial.)  Any idea how to prevent the Mini from waking up when I turn on the DAC?