I gotta say, its very straightforward and effective.
I found nothing but great reviews about DD's waterblocks, so I got this one to OC my new i7 920. Right now I have it cooled using a fountain pump, this block and a 5gallon plastic bucket for a reservoir(passive cooloff till I get a radiator). ;) My temps are +10c ambiant, +20c loaded @ 3.8 after 1 hour duration, no radiator! Its rare to get more then your money's worth, but this block is it. Back plate is a nice addition(comes with foam gasket too), but the brass is a must. Enjoy!