This is a hair faster (3%) and a lil cheaper than most of the Sapphires...one of the Sapphires is $5 cheaper
http://www.newegg.com/Product/Product.aspx?Item=N82E168...
Well the stock 280x is 3% slower than the stock 280x
The MSI 280x is 1% slower than the 770
The MSI 770 is 3% faster than the stock 770
So a 4% difference outta the box.... that gap grows in you are overclocking as the 7xx cards have more headroom than the R9s