Thanks guys (jmpa & rsramirez).
Just an update as it's been around 6 full months of using my Haximus Pro (Mac Pro of sorts).
Well, to be honest, it's not done anything wrong. My only regret is not putting a better GPU in there, but hey, I don't play many games and the games that I have played in Windows (Far Cry 3, Crysis 3, Tomb Raider (new one), Skyrim, Remember Me, Hitman Absolution, etc) all look really good and are a massive boost from my Xbox 360 graphics.
I have not had any reason to reinstall osX due to any issues, and it still boots within a few seconnds to osX (and Windows when selected) despite having over 1000 additional fonts installed. Even when I go to change the font (in any app), it takes only a second or 2 to load the full list of fonts I have installed.
Verdict: Worth every penny and more.
My only issue, which I didn't have at the time of the build, is the new Mac Pro which was announced recently at the famous keynote speech.
I like the Mac Pro case, but it's so small and petite. Only time will tell if I end up making a Haximus Pro V2 with that case (if and when they become available through the usual outlets).
Thanks for looking at my build, and hopefully it inspires you or at least gives you some ideas to get your own finished or even started.
Bye.