I found this one for $160 shipped and should be able to get hd5870 speeds pretty easily. I have been using Nvidia as my last 4 video cards: 6800gt/7950GT/8800gts/9800gt. I don't really care about a brand as I usually just go with 'best bang for the buck.' I really wanted to get the HD6950 2gb but I just couldn't justify $300 for a card.
http://www.newegg.com/Product/Product.a ... %20diamond