i can answer the corsair cooling side of things. The H50 and H70 are the same, however the H70 comes with 2 fans, in a push-pull configuration. What you can do however, is add a second fan onto your corsair H50 to make it into a H70 at less cost to you. if you do fork out for the H70, you get a slightly larger radiator and a selectable 1600 rpm or 2000 rpm for your fans. on 2000rpm, this leads to a 10 degrees cooler temperature than the H50.
the H60 is the newer model, pretty much an improved H50. It just has a custom fan on it, ideal for cooling