Anyone who answers this w/o knowing your MOBO is a fool. So what MOBO do you have?
Normally you'd be correct but in this case looking at the 2 products the 1600 CAS 8's are $5 cheaper and are most likely the same exact modules just binned differently so the choice really doesn't make much difference ! - I'd go with the $5 savings since they are in reality probably the exact same modules just being sold under 2 different product numbers and then either run them at 1333 Cas7 or 1600 Cas8 depending on the system !
Point taken Jaquith, sorry I didn't include that information.
I don't physically own the motherboard yet, but as of now I'm considering either the ASUS Sabretooth X58 or if I decide to get a little pricier a Rampage III Gene or Formula. Either of these will support a 1600 clock and are triple channel.