Here are some of the benefits of UEFI, and I've gotten Windows 8 running with UEFI on a brand new Seagate Momentus XT disk. One difference i see is that the boot screen is different (I get the ROG icon when booting instead of the standard Windows icon), and frankly anything that gives me faster boot is a plus.
Here's what I found on another site:
Enterprise management: Thanks to support for third party drivers and applications, your IT staff can remotely manage systems equipped with UEFI without booting into Windows or any other OS! This enables you to have a common infrastructure for managing computers across your entire network. Obviously, this is a money saver: Imagine fixing computers by remotely turning them on and running UEFI troubleshooting tools or restoring the image from a backup server. It essentially eliminates the need for the classic “system DVD.”
Pre-OS and network security: UEFI’s enhanced networking API allows for a rich network authentication (log-on) in a pre-boot environment. Also, it offers support for TPM and and authenticode signatures. It’s simply an additional layer of security.
UEFI is “OS-like:” By default, you have full access to the entire hardware of your computer – Ethernet adapter, Wi-Fi, Bluetooth, graphics card, USB, even the audio chip, as well as full blown x86 and x64 support. This enables not only high-resolution UIs, but highly functional pre-boot environments. HP put its System Diagnostics tool (written specifically for UEFI) on laptops and desktops starting in mid-2008.
MSI puts ClickBios on its board, a UEFI environment with some basic maintenance, diagnostics and Instant-On environments (for gaming, multimedia etc.). Unfortunately, that MSI mainboard – based on the P45 chipset – has been discontinued.
Note, these interfaces aren’t mandatory. Some manufacturers may build beautiful UIs in their UEFI environment; some may just skip the UI aspect entirely.
Faster boot and resume times: UEFI handles devices initialization within seconds. This increases IT staff productivity (and user impatience), especially if your business requires rebooting or going in and out of hibernation a lot.
Support for HDDs with more than 2.1 TBytes: UEFI solves this problem by introducing the newer partition table called GUID (global unique identifier), which is finally capable to address more than 2 terabytes of storage. Bottom line: If your business revolves around having huge amounts of data on your PC client, investing in UEFI-capable hardware is a no-brainer.
Specialized UEFI applications: Without the need to boot into an OS, your IT workers could have fast access to their important data – providing that either your IT department or the OEM implements the add-in (see below). Possible scenario: Your staff can quickly glance at their Outlook e-mails or calendars without booting up the notebook. UEFI and its applications are on-screen within seconds.
