Does anyone know if the HiPerfTimer or the StopWatch class is better for benchmarking, and why?
They are the same when it comes to high resolution timing.
Both use this:
[DllImport("Kernel32.dll")]
private static extern bool QueryPerformanceCounter(out long PerformanceCount);
and this:
[DllImport("Kernel32.dll")]
private static extern bool QueryPerformanceFrequency(out long Frequency);
to do the underlying timing. (You can verify this with Reflector.NET). I'd use StopWatch because it's part of the framework already (no need to link another dll) and it had better features than HiPerfTimer.