There is no big difference in the prices , the biggest difference would be about 25$
I would go with any of these: CORSAIR DOMINATOR 6GB (3 x 2GB) DDR3 1600 CL7 Triple Channel Kit Mushkin Enhanced Redline 6GB DDR3 1600 CL6 Triple Channel Kit G.SKILL TRIDENT 6G (3 X 2G)DDR3 BUS 1600 CL7
Whatever you do don't buy any OCZ, they stink in recent years. Also get ram with a 7 latency or less. the smaller the number the better.