What do the benchmarks show? Well, nothing bad, and given the size of the Rampage III Gene, that's a good start.
It keeps up with a full size X58 motherboard, in the shape of Asus' bargainous P6X58D-E, slightly slower in some places and slightly quicker in others. What's important is that these are only base speeds. Overclocked, it performed even better.
HD Video Encoding Performance
3D Rendering Performance
Motherboard Gaming Performance (Low graphics, high physics)