The differences between Ares vs Ripjaws X are the addition of JEDEC (SPD) to match the XMP profile(s) on some of their kits. This makes i.e. AMD more plug-n-play compatible with the 'FX' and newer AMD CPUs. Obviously, the Ares are low-profile so they can more readily fit underneath more HSF. Though the Ripjaws X and Z fit under even the Noctua NH-D14.
One thing that I do NOT like with the Ares is G.SKILL's recommended VCCIO/VCCSA voltage of 1.25v. On the SB-E/SB it's not recommended you exceed 1.20v, 1.00v is default, and >1.35v is proven to degrade the SB-E/SB CPU permanently. In contrast the new lines of Corsair are all tested with 1.10v with XMP.
Therefore, IMO on SB-E/SB/IB CPUs stay away from the Ares.
ref - (from G.SKILL's site); note Step #4 and all of the yellowed (warning voltages) - https://docs.google.com/document/pub?id=17VKzOB5CL5EtIelw5tGsj2CqjBk3O0OU5VPe6CUoFso&pli=1