So, how important are the heat sinks for the 400s do you guys feel? I bought early... (so I have a rev 1.0 res) and am hoping I won't be regretting it. I moved so it's been sitting on a shelf for a few months (along with 2 400 pumps) but I'm planning to install here shortly. I also assumed that the water flow itself would keep the pumps safely cool. Thoughts?