Looks like you and I are going the same direction
I am getting ready for a build, as I am generations behind, and Ivy Bridge is what convinced me that it is the time to upgrade.
I am also going with Case Labs M8/M10, multiple WD Cav Black 7200rpm 1TB HDDs (RAID10), and a set of optical drives although I am very heavily leaning towards two slim drives (a BD-burner, and a BD-reader/DVD+CD burner) as I want to fit both in one 5.25 bay. Even though the case is certainly not lacking in space, I would have an extra free bay for holding pumps/res/storage drives. That means fewer drive bays up front blocking airflow across the motherboard (even though it will be fully under water, I find good case airflow is still a necessity, both for cooling non-H20 parts, and for pumping the coolest air possible through multiple large rads in push pull).
Best of luck with your build!