asus and msi are pretty good especially with cooling and overclocking. i would recomend the MSI Radeon HD7970 Lightning BE 3GB, because it is stocked clocked at 1070mhz, and has an unlocked bios which makes it really good for overclocking. it has 3gb of v-ram which is more than enough. it's got 4 mini display ports and a 348 bit memory interface which is really good if your plaing to do multi-monitor gaming.
diamond and saphhire are long time greats for AMD as well
Personally if I was looking for an AMD card this is what I would choose...
If I want the best bang for my buck I will look at a Saphhire card, those guys are legendary in my eye.
If I want the best period (IMO) I will throw extra money at an ASUS card.
Even though I am primarily an Nvidia user. I have an active AMD machine and have used AMD cards and service in the past.