Basically LGA 2011 is designed to bring workstation power to the desktop or to be the highest end of gaming machines. Or a combination of both. Everything about it costs more from the motherboards to the quad channel RAM to the CPUs. If it's a professional machine you use to make money it will pay for itself in sheer power though.
Think it depends on your needs and what your doing, and since there is no true quad channel DRAM, closest being 8 stick sets which simply have XMP set for 8 sticks (and cost more because it's more difficult to pair up 8 sticks that will play together,i.e testing takes longer than a 2, 3 or 4 stick set), any 4 stick set will run fine on X79