PC-BSD 8.0 vs. Kubuntu 9.10 Benchmarks
Kubuntu was more than 20% faster than PC-BSD with the OpenMP-powered GraphicsMagick test, but this may be attributable to differences in the OpenMP support in GCC between the 4.2 and 4.4 releases.
Kubuntu was just shy of being 10% faster than PC-BSD with the Himeno Poisson Pressure Solver.