Which software gets the fastest rendering times?
I'm not sure that it is necessarily possible to get meaningful benchmarks for video editing render times now.  With the advent of system's using GPU processing for rendering, the already complicated field got even tougher.  There are simply too many variables.  It depends on the performance of particular effects and plugins and what kind of hardware and bandwidth needs there are within the project.  Since the needs of projects differ so greatly, I don't see how a meaningful benchmark could be established unless it was to try benchmarking individual filters within the applications.

In general, the new render engine in Premiere is very fast though.  Even for software only it works quick, but with GPU acceleration, it gets pretty crazy.  Running software only, I can run a full resolution all I frame 1080p 24fps signal with color correction applied through my tower with fairly minimal frame drops.  I'm unfortunately PC only so I can't compare to FCPX.