4x GSkill 2133 VS 2x GSkill1600 ?

[nullkuhl]

1- GSkill DDR3-2133 CL9 4GB(2GBx2) 1.65v
2- GSkill Sniper DDR3-1600 CL9 8GB(4GBx2) 1.35v

Which should i get ? (not that if i buy choice1, i will have to get 2x of it, to make a total of 8 GB, which will cost almost double of choice 2

It's for a sandybridge setup on a p67 ASUS maximus iv board
I do massive gaming, GPGPU programming (Cuda,opencl), and 3d rendering

[EniGmA1987]

SB works best with higher MHz. Higher the better