It's not free, but I've used perl2exe for the last five years. In a recent comparison, a Perl/Tk app started more than six seconds faster (time from icon double-click to mainwindow complete and accepting events) when compiled with perl2exe vs PAR.
I believe that there will be a delay the first time you run a new PAR executable, as it unpacks the contents to some temporary directories. I also believe that the temporary directories will still be there when you rerun.
In this case, I don't think your comparison is fair, unless you are noting a six second delay on second and subsequent activations.
Needless to say, housekeeping could remove the temporary files, and a new version of the .EXE will generate a complete new set of temporary files.
I've also used perl2exe to compile Perl/Tk apps for a few years now with a lot of success. The only problem I've ever run into is that it doesn't always find all the packages it needs, so once and a while you have to throw in a redundant "use PackageName" in your script so perl2exe can find it.
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