Just like the non-Crossfire version, the PI-A9RD480 is a great overclocker board with loads of features. The set of options in the BIOS is exemplary. For example the voltages can be increased far enough, even to make the phase-change coolers happy.
Unlike the more expensive Crossfire motherboard from DFI, the board from Sapphire is certified by ATI for Crossfire, which has suddenly become very important with all the problems people are having with the DFI boards.
While the price is a tad high, it is still the cheapest enthusiast AMD64 board which supports Crossfire. If you decide you need Crossfire, you will have to pay for the higher performance.