I've Heard the HIS IceQ is good and the sapphire is good aswell. Also the Gigabyte version has great reviews and 3 fans.
Doesn't matter.
Like boov said, it really doesn't matter. The biggest difference is going to be the cooler, and MSI makes the best coolers, imo. XFX also gives you a double lifetime warranty, so there's that to consider too.
I'm gonna say either 7870s made by Gigabyte, Sapphire, His and ASUS. They make good coolers and are generally reliable. I'm still wary about MSI, as with the case with their NVidia cards, so I can't say anything about it. But as the others said before me, it really doesn't matter THAT much. It's more of a matter of preference. And I prefer non-reference versions.