Whoa down there killer, the HC blocks are actually very good performers. They are made by swiftech and flow right in line with all the other blocks on the market (the low flow ones were the ancient orignal HC's for the GTX 2xx series). The only downfall to them is that they do not cool the VRM's and they are somewhat pricey. At the same time, they look better than 99% of the other blocks available and come with a kit including the low profile brackets (also can be RMA'd with the card under EVGA warranty). If I could find some HC's for my 580's right now at a decent price I would pick them up.