When comparing Gemini 2 vs AllDup, the Slant community recommends AllDup for most people. In the question“What are the best software tools to find duplicate files?” AllDup is ranked 1st while Gemini 2 is ranked 10th. The most important reason people chose AllDup is:
Keep only earliest copy, for instance.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Ease of use through good UI design
Pro Finds similar photos and removes them in one go
Pro Select files by date
Keep only earliest copy, for instance.
Pro Find similar images
Can find similar but not identical images, using aHash, dHash, or pHash
Pro Select files for deletion based on folder tree
You can select any point in a folder tree and mark all files nested within that tree for modification or deletion
Pro Ignore EXIF or ID3 tags when comparing files
So you can find duplicates of the same MP3 even if the metadata tags have been edited, for instance.
Cons
Con Useful for pictures, but not for complex file/folder structures
Comparing two folders with fonts needs more time and interaction than doing it by hand.
Con One trick pony
Can't do things like merge, or only show orphans.