Indeed running a benchmark is the only way to be sure, but ... looks can be deceiving as repeatedely running a script which reads a file may "suffer" from caching effects in the OS; i.e. the first time you read the file may take a relatively long time and all reads thereafter may be from the cache and hence much faster.
CountZero
"If you have four groups working on a compiler, you'll get a 4-pass compiler." - Conway's Law