I'm surprised no benchmarks were done with logging turned on.
I get wanting to isolate things but this is the problem with micro benchmarks, it doesn't test "real world" usage patterns. Chances are your real production server will be logging to at least syslog so logging performance is worth looking into.
If one of them can write logs with 500 microseconds added to reach request but the other takes 5 milliseconds that could be a huge difference in the end.