I will vouch for Asus motherboards because of the quality and overall craftsmanship of the board. My Asus board is the P8-z77-v LK Version and i love it. both the Asus motherboards you linked are almost exactly the same give or take a feature or two.
All i have is good reviews for Asus when it comes to these boards. Not only does it look nice in my case but its features are awesome too. The color scheme also is a nice added bonus and went well with my ram and GPU.
Asrock makes nice boards too and the bang for your buck is pretty good with them. However i would still recommend the Asus boards.
The bios is the best iv ever used. with full mouse and keyboard control its like running an OS, includes a basic and advanced mode for your skillset. This was very useful and also a nice addition. Also supports Windows 8.
Overclocking is no problem with these motherboards and i recommend doing so. Just remember to pick up a nice CPU cooler to keep the temps down.