i have the leadtek and it;s really cool idle and under load (i haven't tried OCing yet)
however, i've also heard a lot of great things about eVGA; it all depends on you (i just checked newegg and the evga pci-e is pretty cheap right now ($17x) compared to my $205 leadtek)
oh and don't mind the lack of software with the evga, because the leadtek package isn't that good either