Well if it'll help you make the decision... I recommend going with ASUS. However... either board are good and the board that suits you will depend on your needs and what you want out of it.
The DFI board you mention is known to be overclocker-friendly and provides loads upon loads of options within the BIOS to fully tweak your system for the utmost optimal performance one can gain out of it. If you plan on overclocking heavily or want the absolute highest performance you can gain, this is it.
On the other end of the spectrum, ASUS is, to me, considered to be the Lexus of motherboard -- expensive and high quality. Though one can debate about that, we'll stick with the topic. The ASUS board you mentioned is, of course, high-end and does feature two PCI Express x16 slots regardless of card configuration. It is currently questionable as to whether or not this is truly needed, as we have yet to find anything that is able to take advantage of the X16 bus/bandwidth for gaming applications. It is the best you can get. But one can question if it's needed. If you plan on upgrading regularly, then it's not a good idea to get a board like this, as something better will always come eventually. If you don't plan on getting anything for a long time, then maybe the ASUS board may be worth it to you in the long run.
In either case, your choice is dependent on your needs. Other people will recommend one over the other. But my suggestion is to take a practical look at your options and weigh in the factors to help come to your decision.
For reference, you can
view this link to help come to a better conclusion as to which board is right for you. Good luck and let us know what your final choice is. I, for one, will say it's a good board no matter what you choose.
