You'd have to tune to system so you'd get the right amount of flow to each of the heads for whatever load they happen to be under, and I'm not quite sure how that would work with 4 processors which would all be at different loads depending on what you're running, unless you did something like throwing TEVs on every line. Not impossible, but I imagine the system would be a real headache all the way through the build.

Plus you're going to need a a pretty beefy compressor and condenser for the load you're going to be generating. I've seen the Pelican case you're using, assuming this is the system you're talking about, and you're looking at adding a ton of weight to the system.