The bargain hunters around here will tell you that the Asrock is a good board. I have a different opinion, however, and think that unless you are strapped for cash, you should go with Asus or Gigabyte. They are constructed much better than the Asrock boards.
As to your ram question, either configuration is OK.
I recommend CORSAIR Vengeance 99% of the time, quality RAM and low profile with XMP profile. And if u will get an aftermarket CPU cooler, low profile is the worry free remedy with perfect fit with any large cooler.
CORSAIR Vengeance 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600 http://www.newegg.com/Product/Product.aspx?Item=N82E168...
Vengeance Low Profile heat spreaders have a reduced height of 1.03" (26.25mm). They're designed for high-performance systems with extra-large CPU coolers, small form factor system builds, or any other space-constrained application where standard Vengeance memory might not fit.