Thanks all, I appreciate it, I think that I've decided to go with the ASRock X58 Extreme, it really seems like a well-though-out board for an excellent price.
That said, there's been one board that's been nagging me from the beginning, since I saw it win Anandtech's mid-level comparisons, and the xbitlabs review of it, the Asus P6T Deluxe (which I found for $250). Despite loving everything that was said about the board, I couldn't see how it's worth $80 more than the ASRock X58 Extreme unless someone really wanted to push their CPU and RAM as far as possible (in which case they might probably go for an even more expensive board anyway). Still, it comes back to mind, and here's why:
While the ASRock Extreme reviews have been incredibly positive, they've been positive for the fantastic value it is, with solid potential at a low cost, and an important note is that many reviewers have had stability issues overclocking that they were able to fix through careful adjustment. The P6T Deluxe, however, beyond I imagine having greater overclocking potential, lower board latency, and better power regulation, seems to be easy to overclock without much effort, the Anandtech and Xbitlabs reviews both commented on how it just works. For a first-time builder like myself, that was a real attraction, especially coupled with overclocking software that seems to be actually effective and useful (although Anandtech commented that while it works great for quick, easy, and mild overclocking, the system does end up devoting more resources than it should just to the app).
So, on the plus note I've decided between the giga UD3R and the ASRock X58 Extreme, in favor of the ASRock (more for just how I feel about it and the 30 bucks saved, the UD3R still seems like a great board for the price).
I'm sorry though to introduce another, and very different, option, and I'm wondering what kind of usage people think would make the P6T Deluxe a better choice even for $80 more than the ASRock X58 Extreme? Or is it never really worth that price difference?
Thanks again for the input!