Pros: BIOS update via USB is excellent, as I used this for a new build with an Intel 4930K CPU. Once assembled, the system wouldn't POST, as the BIOS didn't know what to do with the relatively new 4930K. I downloaded the latest BIOS and used the USB BIOS Flashback mechanism to update and everything was good to go after that.
Cons: Always download the latest drivers from ASUS's web site, as the drivers that ship on the DVD are out of date fairly quickly.
Summary: This is definitely the smallest mobo I have ever owned. It wasn't any more difficult to install than other mobos. The bios are beautifully crafted, and are extremely user friendly. All of the features are logically placed into a few specific tabs. My only regret, which isn't a big deal, are the lack of USB 3.0 connectors which left one of the connections on the front of my case inactive. Well Worth the price, ASUS ROCKS.
Summary: If you have a 4820k, 4930k or 4960x processor you will likely need to update the bios with a flash drive before it will boot, it's not a huge problem it's just frustrating because I was just about to begin the RMA process for the board and CPU before I realized that was the issue, especially since red CPU and Q-LED 00 normally means DOA or motherboard.
Pros: Good board if it has what you want, lots of nice little extra features not found on other manufacturers boards. Not very expandable but what you would expect from an ATX micro board.
Cons: Did not come with a BIOS version that supported many of the LGA-2011 CPUs, so you need to update it. This is probably causing a lot of the issues in many of these recent negative reviews so take that into account(namely the ones where it doesn't POST with a red CPU-LED, and Q-LED 00).