To be honest the Msi had a slightly better set up for offset control etc but the Asus has a better layout and feature integration. Things like fan expert etc are streamlined well. The Asus is easy enough to tweak and has slightly more in-depth control inside the 'tweakers paradise' menu or what ever it is called though. I haven't messed with all of that power and phase control etc, no need really.
The things that sold the board for me are, features like keybot, fan expert, supreme fx audio and sonic radar.
With regards to sonic radar, I was not expecting a great deal from this as I thought it was just a gimmick but actually works quite well with its overlay.
Bear in mind the M.2 slot is Pcie only so none of the currently available M.2 drives that use Ahci will work, the flipside to this though is that when compatible drives are released they will offer better performance over currently available ones not only through raw speed but by negating the need for the poorly performing MS Ahci drivers in windows 8.1.
SupremeFX 2014, The onboard sound is pretty darn good actually. I have come from using a Asus Xonar DG. The sound quality and feature set of the supremeFX offer a lot of customization with some apparently at a hardware opamp lvl, the built in headphone amp still does a great job of driving the headphones and the sound quality for on-board is great. The virtual surround works very well, I would say as good as the dolby headphone feature of the DG. All this said the dedicated sound card will always be the better option though.
The supremeFX doesn't quite do as good a job and I put this down to the amplifier and nothing else, the DG offers more raw power and it shows in the low end, bass doesn't quite pack the punch you want (I want) and almost sounds as though the onboard headphone amp runs out of power in the low end when playing bass heavy tracks and the rest of the range drops off to compensate trying to achive almost a 'pseudo bass?'. I will be continuing to use this but if I start to listen to more music I will be breaking out my DIY lm3886 amp and getting a DAC to drive some speakers, I have just built a pc after 12 months of not having one so im just gauging my usage, for games though it will work just fine and headphones will do the trick.
Hope that helps/