As I noted when reviewing A Better Finder Rename (ABFR), both it and Name Mangler are solid, powerful tools for batch-renaming files. In that review, I gave ABFR a slight edge over Name Mangler for the clarity of its interface. It also provides a few options that Name Mangler doesn't, such as the capability to sort files by two criteria rather than just one before renaming them sequentially, and more fine-grained control when searching for and replacing a specific string of text.
But Name Mangler remains the more powerful tool, thanks in large part to its Advanced mode. If you're a power user, and you're willing to put in the time to learn that mode, Name Mangler will be your renamer of choice. Even if you aren't, you may prefer it for the relative compactness of its interface and its fast, efficient performance.
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