Obviously when overclocked the DFI comes out slower due to its limited performance overhead, although quite comically it's still faster than the Asus P7P55D Deluxe. At stock speeds it certainly holds its own, with a mid-high table total performance and latency.
SiSoftware Sandra Lite 2009 SP4 (15.125) Pro Business
Sisoft Sandra tells much the same story - overclocked the DFI is undoubtedly slower, but at stock speeds it certainly approaches the fastest P55 boards in the table.