DDR3 1333mhz CAS 7 vs 1600 mhz CAS 8

Go with the OCZ one, in my experience 1600 cas 8 beats 1333 cas 7 in the builds i have done.

fair enough. Heat production differences are minimal enough to even be considered correct?

Yeah, i'll probably go with the OCZ's too. kinds of prefer lower Cas ratings to clock speeds though. That said maybe a little off topic (apologies TS) , which of these is faster ?

7-7-7-20 2T pr 7-7-7-24 1T ? say both are of the same rams but able to run on either CAS configs.