The Gigabyte is what I have and it is a reliable card. The core doesn't get hot unlike Palit (crap) and has VRM cooling (rare only Zotak besides Gigabyte has that). The noise is next to nothing and is much more quiet than my case fans. None however has vram cooling. AVOID Palit no matter what they are the worst GTX 460 on the market and they have a lot of problems. on Newegg on wrote that some of the fins on the fan broke and most complained about not having any cooling on the vrm.
The Hawk and Cyclone has no VRM cooling either and only have good core cooling however watch your volts as I have found a Hawk that failed when the owner pushed it over 1ghz core at 1.28v. The card died... If you get the Cyclone get some Zalman ramsinks to cool the VRM and every GTX 460 needs cooling back there due to their designs. I am not sure how hot the GTS 450 runs though back there but it can't be all that great either.