I tested some other file name sanitize plugins, but this is the only one which I had absolutely no issues with. File names get sanitized in a way I expect it (like "ä" gets "ae" and not "-" like other plugins handle it). Also, Wordpress features like suffixing of file names if a file name is duplicate still works. It's just a great little plugin, thanks for sharing it with us.
WP Sanitize File Name Plus might not have many installs, but that does not change, that its one of the most useful small plugins I install every time I create a new site, to ensure sane and friendly filenames on uploaded media, be it images or pdf files. Highly recommended. Hoping for af WP 4.5 verification and update any time soon! 😀