I've checked through the site's Programs & Utilities section, the modding tools/programs section and done a search of the create forums and didn't find anything so if what I'm about to ask has already been answered - please point me to the proper thread.

I'm looking for a program that will take two or more packages, compare the contents, and create a report of what the differences are. If the program has the option of letting you choose which differences to merge and create a new file - that would be awesome but not needed.

I know you can open files in s3pe, but the only way I know of comparing the contents is to open each package in a different window and look through each line hoping to spot any differences. Also, any merging I've done with S3PE has taken the contents of the resource from the 2nd file and overwritten the contents of the 1st file's resources - which isn't what I'm looking for.

Any idea if a program like this has been created yet, or do I have to keep doing the comparisons the hard way?

QADPE has this functionality, though it's not perfect: http://www.modthesims.info/showthread.php?t=358694

While this is a nice place to start (and I'll be using it for other file comparisons) it doesn't seem to help much if I'm trying to find the differences between Sims MX's old recategorized store items, Clara's newest unlocked stencils, and the various Store items made LN shiftable.